Merge "Change call to mmap64."
diff --git a/adb/client/transport_mdns.cpp b/adb/client/transport_mdns.cpp
index 2b6aa7c..c9993b7 100644
--- a/adb/client/transport_mdns.cpp
+++ b/adb/client/transport_mdns.cpp
@@ -144,7 +144,7 @@
         return initialized_;
     }
 
-    virtual ~AsyncServiceRef() {
+    void DestroyServiceRef() {
         if (!initialized_) {
             return;
         }
@@ -152,9 +152,13 @@
         // Order matters here! Must destroy the fdevent first since it has a
         // reference to |sdRef_|.
         fdevent_destroy(fde_);
+        D("DNSServiceRefDeallocate(sdRef=%p)", sdRef_);
         DNSServiceRefDeallocate(sdRef_);
+        initialized_ = false;
     }
 
+    virtual ~AsyncServiceRef() { DestroyServiceRef(); }
+
   protected:
     DNSServiceRef sdRef_;
 
@@ -203,6 +207,7 @@
         if (ret != kDNSServiceErr_NoError) {
             D("Got %d from DNSServiceGetAddrInfo.", ret);
         } else {
+            D("DNSServiceGetAddrInfo(sdRef=%p, hosttarget=%s)", sdRef_, hosttarget);
             Initialize();
         }
 
@@ -223,7 +228,7 @@
         return true;
     }
 
-    void Connect(const sockaddr* address) {
+    bool AddToServiceRegistry(const sockaddr* address) {
         sa_family_ = address->sa_family;
 
         if (sa_family_ == AF_INET) {
@@ -234,13 +239,13 @@
             addr_format_ = "[%s]:%hu";
         } else {  // Should be impossible
             D("mDNS resolved non-IP address.");
-            return;
+            return false;
         }
 
         // Winsock version requires the const cast Because Microsoft.
         if (!inet_ntop(sa_family_, const_cast<void*>(ip_addr_data_), ip_addr_, sizeof(ip_addr_))) {
             D("Could not convert IP address to string.");
-            return;
+            return false;
         }
 
         // adb secure service needs to do something different from just
@@ -264,19 +269,32 @@
         }
 
         int adbSecureServiceType = serviceIndex();
+        ServiceRegistry* services = nullptr;
         switch (adbSecureServiceType) {
             case kADBTransportServiceRefIndex:
-                sAdbTransportServices->push_back(this);
+                services = sAdbTransportServices;
                 break;
             case kADBSecurePairingServiceRefIndex:
-                sAdbSecurePairingServices->push_back(this);
+                services = sAdbSecurePairingServices;
                 break;
             case kADBSecureConnectServiceRefIndex:
-                sAdbSecureConnectServices->push_back(this);
+                services = sAdbSecureConnectServices;
                 break;
             default:
-                break;
+                LOG(WARNING) << "No registry available for reg_type=[" << regType_ << "]";
+                return false;
         }
+
+        if (!services->empty()) {
+            // Remove the previous resolved service, if any.
+            services->erase(std::remove_if(services->begin(), services->end(),
+                                           [&](std::unique_ptr<ResolvedService>& service) {
+                                               return (serviceName_ == service->serviceName());
+                                           }));
+        }
+        services->push_back(std::unique_ptr<ResolvedService>(this));
+
+        return true;
     }
 
     int serviceIndex() const { return adb_DNSServiceIndexByName(regType_.c_str()); }
@@ -291,7 +309,7 @@
 
     uint16_t port() const { return port_; }
 
-    using ServiceRegistry = std::vector<ResolvedService*>;
+    using ServiceRegistry = std::vector<std::unique_ptr<ResolvedService>>;
 
     // unencrypted tcp connections
     static ServiceRegistry* sAdbTransportServices;
@@ -321,13 +339,13 @@
 };
 
 // static
-std::vector<ResolvedService*>* ResolvedService::sAdbTransportServices = NULL;
+ResolvedService::ServiceRegistry* ResolvedService::sAdbTransportServices = NULL;
 
 // static
-std::vector<ResolvedService*>* ResolvedService::sAdbSecurePairingServices = NULL;
+ResolvedService::ServiceRegistry* ResolvedService::sAdbSecurePairingServices = NULL;
 
 // static
-std::vector<ResolvedService*>* ResolvedService::sAdbSecureConnectServices = NULL;
+ResolvedService::ServiceRegistry* ResolvedService::sAdbSecureConnectServices = NULL;
 
 // static
 void ResolvedService::initAdbServiceRegistries() {
@@ -348,7 +366,7 @@
                                      adb_secure_foreach_service_callback cb) {
     initAdbServiceRegistries();
 
-    for (auto service : services) {
+    for (const auto& service : services) {
         auto service_name = service->serviceName();
         auto reg_type = service->regType();
         auto ip = service->ipAddress();
@@ -366,7 +384,7 @@
 bool ResolvedService::connectByServiceName(const ServiceRegistry& services,
                                            const std::string& service_name) {
     initAdbServiceRegistries();
-    for (auto service : services) {
+    for (const auto& service : services) {
         if (service_name == service->serviceName()) {
             D("Got service_name match [%s]", service->serviceName().c_str());
             return service->ConnectSecureWifiDevice();
@@ -393,23 +411,28 @@
                                                  service_name);
 }
 
-static void DNSSD_API register_service_ip(DNSServiceRef /*sdRef*/,
-                                          DNSServiceFlags /*flags*/,
+static void DNSSD_API register_service_ip(DNSServiceRef sdRef, DNSServiceFlags flags,
                                           uint32_t /*interfaceIndex*/,
-                                          DNSServiceErrorType /*errorCode*/,
-                                          const char* /*hostname*/,
-                                          const sockaddr* address,
-                                          uint32_t /*ttl*/,
-                                          void* context) {
-    D("Got IP for service.");
+                                          DNSServiceErrorType errorCode, const char* hostname,
+                                          const sockaddr* address, uint32_t ttl, void* context) {
+    D("%s: sdRef=%p flags=0x%08x errorCode=%u ttl=%u", __func__, sdRef, flags, errorCode, ttl);
     std::unique_ptr<ResolvedService> data(
         reinterpret_cast<ResolvedService*>(context));
-    data->Connect(address);
+    // Only resolve the address once. If the address or port changes, we'll just get another
+    // registration.
+    data->DestroyServiceRef();
 
-    // For ADB Secure services, keep those ResolvedService's around
-    // for later processing with secure connection establishment.
-    if (data->serviceIndex() != kADBTransportServiceRefIndex) {
-        data.release();
+    if (errorCode != kDNSServiceErr_NoError) {
+        D("Got error while looking up ipaddr [%u]", errorCode);
+        return;
+    }
+
+    if (flags & kDNSServiceFlagsAdd) {
+        D("Resolved IP address for [%s]. Adding to service registry.", hostname);
+        auto* ptr = data.release();
+        if (!ptr->AddToServiceRegistry(address)) {
+            data.reset(ptr);
+        }
     }
 }
 
@@ -459,6 +482,7 @@
 };
 
 static void adb_RemoveDNSService(const char* regType, const char* serviceName) {
+    D("%s: regType=[%s] serviceName=[%s]", __func__, regType, serviceName);
     int index = adb_DNSServiceIndexByName(regType);
     ResolvedService::ServiceRegistry* services;
     switch (index) {
@@ -475,10 +499,15 @@
             return;
     }
 
+    if (services->empty()) {
+        return;
+    }
+
     std::string sName(serviceName);
-    services->erase(std::remove_if(
-            services->begin(), services->end(),
-            [&sName](ResolvedService* service) { return (sName == service->serviceName()); }));
+    services->erase(std::remove_if(services->begin(), services->end(),
+                                   [&sName](std::unique_ptr<ResolvedService>& service) {
+                                       return (sName == service->serviceName());
+                                   }));
 }
 
 // Returns the version the device wanted to advertise,
diff --git a/adb/test_adb.py b/adb/test_adb.py
index 03bdcbd..9912f11 100755
--- a/adb/test_adb.py
+++ b/adb/test_adb.py
@@ -659,14 +659,14 @@
                 print(f"Registering {serv_instance}.{serv_type} ...")
                 with zeroconf_register_service(zc, service_info) as info:
                     """Give adb some time to register the service"""
-                    time.sleep(0.25)
+                    time.sleep(1)
                     print(f"services={_mdns_services(server_port)}")
                     self.assertTrue(any((serv_instance in line and serv_type in line)
                         for line in _mdns_services(server_port)))
 
                 """Give adb some time to unregister the service"""
                 print("Unregistering mdns service...")
-                time.sleep(0.25)
+                time.sleep(1)
                 print(f"services={_mdns_services(server_port)}")
                 self.assertFalse(any((serv_instance in line and serv_type in line)
                     for line in _mdns_services(server_port)))
diff --git a/debuggerd/Android.bp b/debuggerd/Android.bp
index d67b522..31c2d5d 100644
--- a/debuggerd/Android.bp
+++ b/debuggerd/Android.bp
@@ -169,6 +169,7 @@
         "libdebuggerd/backtrace.cpp",
         "libdebuggerd/gwp_asan.cpp",
         "libdebuggerd/open_files_list.cpp",
+        "libdebuggerd/scudo.cpp",
         "libdebuggerd/tombstone.cpp",
         "libdebuggerd/utility.cpp",
     ],
@@ -176,8 +177,13 @@
     local_include_dirs: ["libdebuggerd/include"],
     export_include_dirs: ["libdebuggerd/include"],
 
-    // Needed for private/bionic_fdsan.h
-    include_dirs: ["bionic/libc"],
+    include_dirs: [
+        // Needed for private/bionic_fdsan.h
+        "bionic/libc",
+
+        // Needed for scudo/interface.h
+        "external/scudo/standalone/include",
+    ],
     header_libs: [
         "bionic_libc_platform_headers",
         "gwp_asan_headers",
@@ -192,7 +198,10 @@
         "liblog",
     ],
 
-    whole_static_libs: ["gwp_asan_crash_handler"],
+    whole_static_libs: [
+        "gwp_asan_crash_handler",
+        "libscudo",
+    ],
 
     target: {
         recovery: {
@@ -206,6 +215,9 @@
         debuggable: {
             cflags: ["-DROOT_POSSIBLE"],
         },
+        experimental_mte: {
+            cflags: ["-DANDROID_EXPERIMENTAL_MTE"],
+        },
     },
 }
 
@@ -256,6 +268,10 @@
         "gwp_asan_headers",
     ],
 
+    include_dirs: [
+        "external/scudo/standalone/include",
+    ],
+
     local_include_dirs: [
         "libdebuggerd",
     ],
@@ -271,6 +287,12 @@
     },
 
     test_suites: ["device-tests"],
+
+    product_variables: {
+        experimental_mte: {
+            cflags: ["-DANDROID_EXPERIMENTAL_MTE"],
+        },
+    },
 }
 
 cc_benchmark {
diff --git a/debuggerd/crash_dump.cpp b/debuggerd/crash_dump.cpp
index 0cd2350..d7cb972 100644
--- a/debuggerd/crash_dump.cpp
+++ b/debuggerd/crash_dump.cpp
@@ -289,6 +289,8 @@
       process_info->fdsan_table_address = crash_info->data.d.fdsan_table_address;
       process_info->gwp_asan_state = crash_info->data.d.gwp_asan_state;
       process_info->gwp_asan_metadata = crash_info->data.d.gwp_asan_metadata;
+      process_info->scudo_stack_depot = crash_info->data.d.scudo_stack_depot;
+      process_info->scudo_region_info = crash_info->data.d.scudo_region_info;
       FALLTHROUGH_INTENDED;
     case 1:
     case 2:
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index 054f836..25417a9 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -31,6 +31,9 @@
 
 #include <android/fdsan.h>
 #include <android/set_abort_message.h>
+#include <bionic/malloc.h>
+#include <bionic/mte.h>
+#include <bionic/mte_kernel.h>
 #include <bionic/reserved_signals.h>
 
 #include <android-base/cmsg.h>
@@ -331,6 +334,173 @@
       R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr (0x100000000000dead|0xdead))");
 }
 
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+static void SetTagCheckingLevelSync() {
+  int tagged_addr_ctrl = prctl(PR_GET_TAGGED_ADDR_CTRL, 0, 0, 0, 0);
+  if (tagged_addr_ctrl < 0) {
+    abort();
+  }
+
+  tagged_addr_ctrl = (tagged_addr_ctrl & ~PR_MTE_TCF_MASK) | PR_MTE_TCF_SYNC;
+  if (prctl(PR_SET_TAGGED_ADDR_CTRL, tagged_addr_ctrl, 0, 0, 0) != 0) {
+    abort();
+  }
+
+  HeapTaggingLevel heap_tagging_level = M_HEAP_TAGGING_LEVEL_SYNC;
+  if (!android_mallopt(M_SET_HEAP_TAGGING_LEVEL, &heap_tagging_level, sizeof(heap_tagging_level))) {
+    abort();
+  }
+}
+#endif
+
+TEST_F(CrasherTest, mte_uaf) {
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([]() {
+    SetTagCheckingLevelSync();
+    volatile int* p = (volatile int*)malloc(16);
+    free((void *)p);
+    p[0] = 42;
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGSEGV);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 9 \(SEGV_MTESERR\))");
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Use After Free, 0 bytes into a 16-byte allocation)");
+#else
+  GTEST_SKIP() << "Requires aarch64 + ANDROID_EXPERIMENTAL_MTE";
+#endif
+}
+
+TEST_F(CrasherTest, mte_overflow) {
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([]() {
+    SetTagCheckingLevelSync();
+    volatile int* p = (volatile int*)malloc(16);
+    p[4] = 42;
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGSEGV);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a 16-byte allocation)");
+#else
+  GTEST_SKIP() << "Requires aarch64 + ANDROID_EXPERIMENTAL_MTE";
+#endif
+}
+
+TEST_F(CrasherTest, mte_underflow) {
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([]() {
+    SetTagCheckingLevelSync();
+    volatile int* p = (volatile int*)malloc(16);
+    p[-1] = 42;
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGSEGV);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 9 \(SEGV_MTESERR\))");
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Underflow, 4 bytes left of a 16-byte allocation)");
+#else
+  GTEST_SKIP() << "Requires aarch64 + ANDROID_EXPERIMENTAL_MTE";
+#endif
+}
+
+TEST_F(CrasherTest, mte_multiple_causes) {
+#if defined(__aarch64__) && defined(ANDROID_EXPERIMENTAL_MTE)
+  if (!mte_supported()) {
+    GTEST_SKIP() << "Requires MTE";
+  }
+
+  int intercept_result;
+  unique_fd output_fd;
+  StartProcess([]() {
+    SetTagCheckingLevelSync();
+
+    // Make two allocations with the same tag and close to one another. Check for both properties
+    // with a bounds check -- this relies on the fact that only if the allocations have the same tag
+    // would they be measured as closer than 128 bytes to each other. Otherwise they would be about
+    // (some non-zero value << 56) apart.
+    //
+    // The out-of-bounds access will be considered either an overflow of one or an underflow of the
+    // other.
+    std::set<uintptr_t> allocs;
+    for (int i = 0; i != 4096; ++i) {
+      uintptr_t alloc = reinterpret_cast<uintptr_t>(malloc(16));
+      auto it = allocs.insert(alloc).first;
+      if (it != allocs.begin() && *std::prev(it) + 128 > alloc) {
+        *reinterpret_cast<int*>(*std::prev(it) + 16) = 42;
+      }
+      if (std::next(it) != allocs.end() && alloc + 128 > *std::next(it)) {
+        *reinterpret_cast<int*>(alloc + 16) = 42;
+      }
+    }
+  });
+
+  StartIntercept(&output_fd);
+  FinishCrasher();
+  AssertDeath(SIGSEGV);
+  FinishIntercept(&intercept_result);
+
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+
+  ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\))");
+  ASSERT_MATCH(
+      result,
+      R"(Note: multiple potential causes for this crash were detected, listing them in decreasing order of probability.)");
+
+  // Adjacent untracked allocations may cause us to see the wrong underflow here (or only
+  // overflows), so we can't match explicitly for an underflow message.
+  ASSERT_MATCH(result, R"(Cause: \[MTE\]: Buffer Overflow, 0 bytes right of a 16-byte allocation)");
+#else
+  GTEST_SKIP() << "Requires aarch64 + ANDROID_EXPERIMENTAL_MTE";
+#endif
+}
+
 TEST_F(CrasherTest, LD_PRELOAD) {
   int intercept_result;
   unique_fd output_fd;
diff --git a/debuggerd/include/debuggerd/handler.h b/debuggerd/include/debuggerd/handler.h
index 6650294..254ed4f 100644
--- a/debuggerd/include/debuggerd/handler.h
+++ b/debuggerd/include/debuggerd/handler.h
@@ -40,6 +40,8 @@
   void* fdsan_table;
   const gwp_asan::AllocatorState* gwp_asan_state;
   const gwp_asan::AllocationMetadata* gwp_asan_metadata;
+  const char* scudo_stack_depot;
+  const char* scudo_region_info;
 };
 
 // These callbacks are called in a signal handler, and thus must be async signal safe.
diff --git a/debuggerd/libdebuggerd/include/libdebuggerd/scudo.h b/debuggerd/libdebuggerd/include/libdebuggerd/scudo.h
new file mode 100644
index 0000000..4d00ece
--- /dev/null
+++ b/debuggerd/libdebuggerd/include/libdebuggerd/scudo.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2020 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.
+ */
+
+#pragma once
+
+#include "types.h"
+#include "utility.h"
+
+#include <memory.h>
+
+#include "scudo/interface.h"
+
+class ScudoCrashData {
+ public:
+  ScudoCrashData() = delete;
+  ~ScudoCrashData() = default;
+  ScudoCrashData(unwindstack::Memory* process_memory, const ProcessInfo& process_info);
+
+  bool CrashIsMine() const;
+
+  void DumpCause(log_t* log, unwindstack::Unwinder* unwinder) const;
+
+ private:
+  scudo_error_info error_info_ = {};
+  uintptr_t untagged_fault_addr_;
+
+  void DumpReport(const scudo_error_report* report, log_t* log,
+                  unwindstack::Unwinder* unwinder) const;
+};
diff --git a/debuggerd/libdebuggerd/include/libdebuggerd/types.h b/debuggerd/libdebuggerd/include/libdebuggerd/types.h
index 35c3fd6..04c4b5c 100644
--- a/debuggerd/libdebuggerd/include/libdebuggerd/types.h
+++ b/debuggerd/libdebuggerd/include/libdebuggerd/types.h
@@ -41,6 +41,8 @@
   uintptr_t fdsan_table_address = 0;
   uintptr_t gwp_asan_state = 0;
   uintptr_t gwp_asan_metadata = 0;
+  uintptr_t scudo_stack_depot = 0;
+  uintptr_t scudo_region_info = 0;
 
   bool has_fault_address = false;
   uintptr_t fault_address = 0;
diff --git a/debuggerd/libdebuggerd/scudo.cpp b/debuggerd/libdebuggerd/scudo.cpp
new file mode 100644
index 0000000..f8bfe07
--- /dev/null
+++ b/debuggerd/libdebuggerd/scudo.cpp
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2020 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 "libdebuggerd/scudo.h"
+#include "libdebuggerd/gwp_asan.h"
+
+#include "unwindstack/Memory.h"
+#include "unwindstack/Unwinder.h"
+
+#include <bionic/macros.h>
+
+std::unique_ptr<char[]> AllocAndReadFully(unwindstack::Memory* process_memory, uint64_t addr,
+                                          size_t size) {
+  auto buf = std::make_unique<char[]>(size);
+  if (!process_memory->ReadFully(addr, buf.get(), size)) {
+    return std::unique_ptr<char[]>();
+  }
+  return buf;
+}
+
+static const uintptr_t kTagGranuleSize = 16;
+
+ScudoCrashData::ScudoCrashData(unwindstack::Memory* process_memory,
+                               const ProcessInfo& process_info) {
+  if (!process_info.has_fault_address) {
+    return;
+  }
+
+  auto stack_depot = AllocAndReadFully(process_memory, process_info.scudo_stack_depot,
+                                       __scudo_get_stack_depot_size());
+  auto region_info = AllocAndReadFully(process_memory, process_info.scudo_region_info,
+                                       __scudo_get_region_info_size());
+
+  untagged_fault_addr_ = untag_address(process_info.fault_address);
+  uintptr_t fault_page = untagged_fault_addr_ & ~(PAGE_SIZE - 1);
+
+  uintptr_t memory_begin = fault_page - PAGE_SIZE * 16;
+  if (memory_begin > fault_page) {
+    return;
+  }
+
+  uintptr_t memory_end = fault_page + PAGE_SIZE * 16;
+  if (memory_end < fault_page) {
+    return;
+  }
+
+  auto memory = std::make_unique<char[]>(memory_end - memory_begin);
+  for (auto i = memory_begin; i != memory_end; i += PAGE_SIZE) {
+    process_memory->ReadFully(i, memory.get() + i - memory_begin, PAGE_SIZE);
+  }
+
+  auto memory_tags = std::make_unique<char[]>((memory_end - memory_begin) / kTagGranuleSize);
+  for (auto i = memory_begin; i != memory_end; i += kTagGranuleSize) {
+    memory_tags[(i - memory_begin) / kTagGranuleSize] = process_memory->ReadTag(i);
+  }
+
+  __scudo_get_error_info(&error_info_, process_info.fault_address, stack_depot.get(),
+                         region_info.get(), memory.get(), memory_tags.get(), memory_begin,
+                         memory_end - memory_begin);
+}
+
+bool ScudoCrashData::CrashIsMine() const {
+  return error_info_.reports[0].error_type != UNKNOWN;
+}
+
+void ScudoCrashData::DumpCause(log_t* log, unwindstack::Unwinder* unwinder) const {
+  if (error_info_.reports[1].error_type != UNKNOWN) {
+    _LOG(log, logtype::HEADER,
+         "\nNote: multiple potential causes for this crash were detected, listing them in "
+         "decreasing order of probability.\n");
+  }
+
+  size_t report_num = 0;
+  while (report_num < sizeof(error_info_.reports) / sizeof(error_info_.reports[0]) &&
+         error_info_.reports[report_num].error_type != UNKNOWN) {
+    DumpReport(&error_info_.reports[report_num++], log, unwinder);
+  }
+}
+
+void ScudoCrashData::DumpReport(const scudo_error_report* report, log_t* log,
+                                unwindstack::Unwinder* unwinder) const {
+  const char *error_type_str;
+  switch (report->error_type) {
+    case USE_AFTER_FREE:
+      error_type_str = "Use After Free";
+      break;
+    case BUFFER_OVERFLOW:
+      error_type_str = "Buffer Overflow";
+      break;
+    case BUFFER_UNDERFLOW:
+      error_type_str = "Buffer Underflow";
+      break;
+    default:
+      error_type_str = "Unknown";
+      break;
+  }
+
+  uintptr_t diff;
+  const char* location_str;
+
+  if (untagged_fault_addr_ < report->allocation_address) {
+    // Buffer Underflow, 6 bytes left of a 41-byte allocation at 0xdeadbeef.
+    location_str = "left of";
+    diff = report->allocation_address - untagged_fault_addr_;
+  } else if (untagged_fault_addr_ - report->allocation_address < report->allocation_size) {
+    // Use After Free, 40 bytes into a 41-byte allocation at 0xdeadbeef.
+    location_str = "into";
+    diff = untagged_fault_addr_ - report->allocation_address;
+  } else {
+    // Buffer Overflow, 6 bytes right of a 41-byte allocation at 0xdeadbeef.
+    location_str = "right of";
+    diff = untagged_fault_addr_ - report->allocation_address - report->allocation_size;
+  }
+
+  // Suffix of 'bytes', i.e. 4 bytes' vs. '1 byte'.
+  const char* byte_suffix = "s";
+  if (diff == 1) {
+    byte_suffix = "";
+  }
+  _LOG(log, logtype::HEADER,
+       "\nCause: [MTE]: %s, %" PRIuPTR " byte%s %s a %zu-byte allocation at 0x%" PRIxPTR "\n",
+       error_type_str, diff, byte_suffix, location_str, report->allocation_size,
+       report->allocation_address);
+
+  if (report->allocation_trace[0]) {
+    _LOG(log, logtype::BACKTRACE, "\nallocated by thread %u:\n", report->allocation_tid);
+    unwinder->SetDisplayBuildID(true);
+    for (size_t i = 0; i < 64 && report->allocation_trace[i]; ++i) {
+      unwindstack::FrameData frame_data =
+          unwinder->BuildFrameFromPcOnly(report->allocation_trace[i]);
+      frame_data.num = i;
+      _LOG(log, logtype::BACKTRACE, "    %s\n", unwinder->FormatFrame(frame_data).c_str());
+    }
+  }
+
+  if (report->deallocation_trace[0]) {
+    _LOG(log, logtype::BACKTRACE, "\ndeallocated by thread %u:\n", report->deallocation_tid);
+    unwinder->SetDisplayBuildID(true);
+    for (size_t i = 0; i < 64 && report->deallocation_trace[i]; ++i) {
+      unwindstack::FrameData frame_data =
+          unwinder->BuildFrameFromPcOnly(report->deallocation_trace[i]);
+      frame_data.num = i;
+      _LOG(log, logtype::BACKTRACE, "    %s\n", unwinder->FormatFrame(frame_data).c_str());
+    }
+  }
+}
diff --git a/debuggerd/libdebuggerd/tombstone.cpp b/debuggerd/libdebuggerd/tombstone.cpp
index d6b2e25..ab65dd1 100644
--- a/debuggerd/libdebuggerd/tombstone.cpp
+++ b/debuggerd/libdebuggerd/tombstone.cpp
@@ -56,6 +56,7 @@
 #include "libdebuggerd/backtrace.h"
 #include "libdebuggerd/gwp_asan.h"
 #include "libdebuggerd/open_files_list.h"
+#include "libdebuggerd/scudo.h"
 #include "libdebuggerd/utility.h"
 
 #include "gwp_asan/common.h"
@@ -389,14 +390,17 @@
   }
 
   std::unique_ptr<GwpAsanCrashData> gwp_asan_crash_data;
+  std::unique_ptr<ScudoCrashData> scudo_crash_data;
   if (primary_thread) {
     gwp_asan_crash_data = std::make_unique<GwpAsanCrashData>(unwinder->GetProcessMemory().get(),
                                                              process_info, thread_info);
+    scudo_crash_data =
+        std::make_unique<ScudoCrashData>(unwinder->GetProcessMemory().get(), process_info);
   }
 
   if (primary_thread && gwp_asan_crash_data->CrashIsMine()) {
     gwp_asan_crash_data->DumpCause(log);
-  } else if (thread_info.siginfo) {
+  } else if (thread_info.siginfo && !(primary_thread && scudo_crash_data->CrashIsMine())) {
     dump_probable_cause(log, thread_info.siginfo, unwinder->GetMaps(),
                         thread_info.registers.get());
   }
@@ -427,6 +431,8 @@
       gwp_asan_crash_data->DumpAllocationTrace(log, unwinder);
     }
 
+    scudo_crash_data->DumpCause(log, unwinder);
+
     unwindstack::Maps* maps = unwinder->GetMaps();
     dump_memory_and_code(log, maps, unwinder->GetProcessMemory().get(),
                          thread_info.registers.get());
diff --git a/debuggerd/libdebuggerd/utility.cpp b/debuggerd/libdebuggerd/utility.cpp
index 3bf28b6..c8a3431 100644
--- a/debuggerd/libdebuggerd/utility.cpp
+++ b/debuggerd/libdebuggerd/utility.cpp
@@ -35,6 +35,7 @@
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
+#include <bionic/mte_kernel.h>
 #include <bionic/reserved_signals.h>
 #include <debuggerd/handler.h>
 #include <log/log.h>
@@ -374,6 +375,12 @@
           return "SEGV_ADIDERR";
         case SEGV_ADIPERR:
           return "SEGV_ADIPERR";
+#if defined(ANDROID_EXPERIMENTAL_MTE)
+        case SEGV_MTEAERR:
+          return "SEGV_MTEAERR";
+        case SEGV_MTESERR:
+          return "SEGV_MTESERR";
+#endif
       }
       static_assert(NSIGSEGV == SEGV_ADIPERR, "missing SEGV_* si_code");
       break;
diff --git a/debuggerd/protocol.h b/debuggerd/protocol.h
index e85660c..53a76ea 100644
--- a/debuggerd/protocol.h
+++ b/debuggerd/protocol.h
@@ -95,6 +95,8 @@
   uintptr_t fdsan_table_address;
   uintptr_t gwp_asan_state;
   uintptr_t gwp_asan_metadata;
+  uintptr_t scudo_stack_depot;
+  uintptr_t scudo_region_info;
 };
 
 struct __attribute__((__packed__)) CrashInfo {
diff --git a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
index 5acd039..2d6071f 100644
--- a/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
+++ b/fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
@@ -580,6 +580,10 @@
     bool ProcessUpdateStateOnDataWipe(bool allow_forward_merge,
                                       const std::function<bool()>& callback);
 
+    // Return device string of a mapped image, or if it is not available, the mapped image path.
+    bool GetMappedImageDeviceStringOrPath(const std::string& device_name,
+                                          std::string* device_string_or_mapped_path);
+
     std::string gsid_dir_;
     std::string metadata_dir_;
     std::unique_ptr<IDeviceInfo> device_;
diff --git a/fs_mgr/libsnapshot/snapshot.cpp b/fs_mgr/libsnapshot/snapshot.cpp
index 03efd68..488009a 100644
--- a/fs_mgr/libsnapshot/snapshot.cpp
+++ b/fs_mgr/libsnapshot/snapshot.cpp
@@ -1691,7 +1691,7 @@
         return false;
     }
     std::string cow_device;
-    if (!dm.GetDeviceString(cow_name, &cow_device)) {
+    if (!GetMappedImageDeviceStringOrPath(cow_name, &cow_device)) {
         LOG(ERROR) << "Could not determine major/minor for: " << cow_name;
         return false;
     }
@@ -1788,7 +1788,7 @@
     // If the COW image exists, append it as the last extent.
     if (snapshot_status.cow_file_size() > 0) {
         std::string cow_image_device;
-        if (!dm.GetDeviceString(cow_image_name, &cow_image_device)) {
+        if (!GetMappedImageDeviceStringOrPath(cow_image_name, &cow_image_device)) {
             LOG(ERROR) << "Cannot determine major/minor for: " << cow_image_name;
             return false;
         }
@@ -2364,7 +2364,6 @@
         const std::map<std::string, SnapshotStatus>& all_snapshot_status) {
     CHECK(lock);
 
-    auto& dm = DeviceMapper::Instance();
     CreateLogicalPartitionParams cow_params{
             .block_device = LP_METADATA_DEFAULT_PARTITION_NAME,
             .metadata = exported_target_metadata,
@@ -2389,7 +2388,7 @@
         }
 
         std::string cow_path;
-        if (!dm.GetDmDevicePathByName(cow_name, &cow_path)) {
+        if (!images_->GetMappedImageDevice(cow_name, &cow_path)) {
             LOG(ERROR) << "Cannot determine path for " << cow_name;
             return Return::Error();
         }
@@ -2742,5 +2741,24 @@
     return SnapshotMergeStats::GetInstance(*this);
 }
 
+bool SnapshotManager::GetMappedImageDeviceStringOrPath(const std::string& device_name,
+                                                       std::string* device_string_or_mapped_path) {
+    auto& dm = DeviceMapper::Instance();
+    // Try getting the device string if it is a device mapper device.
+    if (dm.GetState(device_name) != DmDeviceState::INVALID) {
+        return dm.GetDeviceString(device_name, device_string_or_mapped_path);
+    }
+
+    // Otherwise, get path from IImageManager.
+    if (!images_->GetMappedImageDevice(device_name, device_string_or_mapped_path)) {
+        return false;
+    }
+
+    LOG(WARNING) << "Calling GetMappedImageDevice with local image manager; device "
+                 << (device_string_or_mapped_path ? *device_string_or_mapped_path : "(nullptr)")
+                 << "may not be available in first stage init! ";
+    return true;
+}
+
 }  // namespace snapshot
 }  // namespace android
diff --git a/liblog/README.md b/liblog/README.md
index f64f376..74a2cd7 100644
--- a/liblog/README.md
+++ b/liblog/README.md
@@ -60,8 +60,6 @@
     LOG_EVENT_INT(tag, value)
     LOG_EVENT_LONG(tag, value)
 
-    clockid_t android_log_clockid()
-
     log_id_t android_logger_get_id(struct logger *logger)
     int android_logger_clear(struct logger *logger)
     int android_logger_get_log_size(struct logger *logger)
@@ -119,7 +117,7 @@
 multiple logs can be opened with `android_logger_list_alloc()`, calling in turn the
 `android_logger_open()` for each log id.  Each entry can be retrieved with
 `android_logger_list_read()`.  The log(s) can be closed with `android_logger_list_free()`.
-`ANDROID_LOG_NONBLOCK` mode will report when the log reading is done with an `EAGAIN` error return 
+`ANDROID_LOG_NONBLOCK` mode will report when the log reading is done with an `EAGAIN` error return
 code, otherwise the `android_logger_list_read()` call will block for new entries.
 
 The `ANDROID_LOG_WRAP` mode flag to the `android_logger_list_alloc_time()` signals logd to quiesce
diff --git a/liblog/include/log/log.h b/liblog/include/log/log.h
index 820b7cb..d7e9b7d 100644
--- a/liblog/include/log/log.h
+++ b/liblog/include/log/log.h
@@ -133,12 +133,6 @@
   (void)__android_log_bswrite(_tag, _value);
 #endif
 
-#ifdef __linux__
-
-clockid_t android_log_clockid(void);
-
-#endif /* __linux__ */
-
 /* --------------------------------------------------------------------- */
 
 /*
diff --git a/liblog/logger_write.cpp b/liblog/logger_write.cpp
index 3a75fa3..22c7eca 100644
--- a/liblog/logger_write.cpp
+++ b/liblog/logger_write.cpp
@@ -192,7 +192,7 @@
     return -EINVAL;
   }
 
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   if (log_id == LOG_ID_SECURITY) {
     if (vec[0].iov_len < 4) {
diff --git a/liblog/logprint.cpp b/liblog/logprint.cpp
index 9e8d277..238431f 100644
--- a/liblog/logprint.cpp
+++ b/liblog/logprint.cpp
@@ -216,11 +216,7 @@
   p_ret->year_output = false;
   p_ret->zone_output = false;
   p_ret->epoch_output = false;
-#ifdef __ANDROID__
-  p_ret->monotonic_output = android_log_clockid() == CLOCK_MONOTONIC;
-#else
   p_ret->monotonic_output = false;
-#endif
   p_ret->uid_output = false;
   p_ret->descriptive_output = false;
   descriptive_output = false;
@@ -1465,13 +1461,10 @@
   nsec = entry->tv_nsec;
 #if __ANDROID__
   if (p_format->monotonic_output) {
-    /* prevent convertMonotonic from being called if logd is monotonic */
-    if (android_log_clockid() != CLOCK_MONOTONIC) {
-      struct timespec time;
-      convertMonotonic(&time, entry);
-      now = time.tv_sec;
-      nsec = time.tv_nsec;
-    }
+    struct timespec time;
+    convertMonotonic(&time, entry);
+    now = time.tv_sec;
+    nsec = time.tv_nsec;
   }
 #endif
   if (now < 0) {
diff --git a/liblog/pmsg_writer.cpp b/liblog/pmsg_writer.cpp
index 0751e2c..8e676bd 100644
--- a/liblog/pmsg_writer.cpp
+++ b/liblog/pmsg_writer.cpp
@@ -188,7 +188,7 @@
     return -EINVAL;
   }
 
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   cp = strdup(filename);
   if (!cp) {
diff --git a/liblog/properties.cpp b/liblog/properties.cpp
index 37670ec..f5e060c 100644
--- a/liblog/properties.cpp
+++ b/liblog/properties.cpp
@@ -365,29 +365,6 @@
   return c;
 }
 
-static unsigned char evaluate_persist_ro(const struct cache2_char* self) {
-  unsigned char c = self->cache_persist.c;
-
-  if (c) {
-    return c;
-  }
-
-  return self->cache_ro.c;
-}
-
-/*
- * Timestamp state generally remains constant, but can change at any time
- * to handle developer requirements.
- */
-clockid_t android_log_clockid() {
-  static struct cache2_char clockid = {PTHREAD_MUTEX_INITIALIZER, 0,
-                                       "persist.logd.timestamp",  {{NULL, 0xFFFFFFFF}, '\0'},
-                                       "ro.logd.timestamp",       {{NULL, 0xFFFFFFFF}, '\0'},
-                                       evaluate_persist_ro};
-
-  return (tolower(do_cache2_char(&clockid)) == 'm') ? CLOCK_MONOTONIC : CLOCK_REALTIME;
-}
-
 /*
  * Security state generally remains constant, but the DO must be able
  * to turn off logging should it become spammy after an attack is detected.
diff --git a/liblog/tests/liblog_benchmark.cpp b/liblog/tests/liblog_benchmark.cpp
index f4734b9..a4e4def 100644
--- a/liblog/tests/liblog_benchmark.cpp
+++ b/liblog/tests/liblog_benchmark.cpp
@@ -184,7 +184,7 @@
    */
 
   struct timespec ts;
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   android_pmsg_log_header_t pmsg_header;
   pmsg_header.magic = LOGGER_MAGIC;
@@ -260,7 +260,7 @@
    */
 
   struct timespec ts;
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   struct packet {
     android_pmsg_log_header_t pmsg_header;
@@ -335,7 +335,7 @@
    */
 
   struct timespec ts;
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   struct packet {
     android_pmsg_log_header_t pmsg_header;
@@ -410,7 +410,7 @@
    */
 
   struct timespec ts;
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   struct packet {
     android_pmsg_log_header_t pmsg_header;
@@ -483,7 +483,7 @@
    */
 
   struct timespec ts;
-  clock_gettime(android_log_clockid(), &ts);
+  clock_gettime(CLOCK_REALTIME, &ts);
 
   struct packet {
     android_pmsg_log_header_t pmsg_header;
@@ -792,16 +792,6 @@
 BENCHMARK(BM_is_loggable);
 
 /*
- *	Measure the time it takes for android_log_clockid.
- */
-static void BM_clockid(benchmark::State& state) {
-  while (state.KeepRunning()) {
-    android_log_clockid();
-  }
-}
-BENCHMARK(BM_clockid);
-
-/*
  *	Measure the time it takes for __android_log_security.
  */
 static void BM_security(benchmark::State& state) {
diff --git a/liblog/tests/liblog_test.cpp b/liblog/tests/liblog_test.cpp
index d3d8e91..bbc985a 100644
--- a/liblog/tests/liblog_test.cpp
+++ b/liblog/tests/liblog_test.cpp
@@ -329,8 +329,6 @@
 #ifdef __ANDROID__
   pid_t pid = getpid();
 
-  log_time ts(android_log_clockid());
-
   size_t num_lines = 1, size = 0, length = 0, total = 0;
   const char* cp = message;
   while (*cp) {
@@ -432,7 +430,6 @@
   pid_t pid = getpid();
 
   static const char tag[] = "TEST__android_log_buf_write";
-  log_time ts(android_log_clockid());
 
   auto write_function = [&] {
     EXPECT_LT(0, __android_log_buf_write(LOG_ID_MAIN, ANDROID_LOG_INFO, tag, message));
diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index 8185f01..13023f2 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -459,7 +459,7 @@
                                             closedir);
     if (!dir.get()) return retval;
 
-    log_time now(android_log_clockid());
+    log_time now(CLOCK_REALTIME);
 
     size_t len = strlen(file);
     log_time modulo(0, NS_PER_SEC);
diff --git a/logcat/tests/logcat_test.cpp b/logcat/tests/logcat_test.cpp
index b32b437..3a55c4e 100644
--- a/logcat/tests/logcat_test.cpp
+++ b/logcat/tests/logcat_test.cpp
@@ -174,11 +174,6 @@
 }
 
 TEST(logcat, year) {
-    if (android_log_clockid() == CLOCK_MONOTONIC) {
-        fprintf(stderr, "Skipping test, logd is monotonic time\n");
-        return;
-    }
-
     int count;
     int tries = 3;  // in case run too soon after system start or buffer clear
 
@@ -249,11 +244,6 @@
 }
 
 TEST(logcat, tz) {
-    if (android_log_clockid() == CLOCK_MONOTONIC) {
-        fprintf(stderr, "Skipping test, logd is monotonic time\n");
-        return;
-    }
-
     int tries = 4;  // in case run too soon after system start or buffer clear
     int count;
 
diff --git a/logd/Android.bp b/logd/Android.bp
index b6d30cd..ea1054d 100644
--- a/logd/Android.bp
+++ b/logd/Android.bp
@@ -52,7 +52,9 @@
 
     export_include_dirs: ["."],
 
-    cflags: ["-Werror"] + event_flag,
+    cflags: [
+        "-Wextra",
+    ] + event_flag,
 }
 
 cc_binary {
@@ -75,7 +77,9 @@
         "libcap",
     ],
 
-    cflags: ["-Werror"],
+    cflags: [
+        "-Wextra",
+    ],
 }
 
 cc_binary {
@@ -90,10 +94,8 @@
     shared_libs: ["libbase"],
 
     cflags: [
-        "-Wall",
+        "-Wconversion",
         "-Wextra",
-        "-Werror",
-        "-Wconversion"
     ],
 }
 
diff --git a/logd/LogAudit.cpp b/logd/LogAudit.cpp
index 37067bd..bcc187d 100644
--- a/logd/LogAudit.cpp
+++ b/logd/LogAudit.cpp
@@ -247,22 +247,10 @@
 
     static const char audit_str[] = " audit(";
     char* timeptr = strstr(str, audit_str);
-    if (timeptr &&
-        ((cp = now.strptime(timeptr + sizeof(audit_str) - 1, "%s.%q"))) &&
+    if (timeptr && ((cp = now.strptime(timeptr + sizeof(audit_str) - 1, "%s.%q"))) &&
         (*cp == ':')) {
         memcpy(timeptr + sizeof(audit_str) - 1, "0.0", 3);
         memmove(timeptr + sizeof(audit_str) - 1 + 3, cp, strlen(cp) + 1);
-        if (!isMonotonic()) {
-            if (android::isMonotonic(now)) {
-                LogKlog::convertMonotonicToReal(now);
-            }
-        } else {
-            if (!android::isMonotonic(now)) {
-                LogKlog::convertRealToMonotonic(now);
-            }
-        }
-    } else if (isMonotonic()) {
-        now = log_time(CLOCK_MONOTONIC);
     } else {
         now = log_time(CLOCK_REALTIME);
     }
diff --git a/logd/LogAudit.h b/logd/LogAudit.h
index c3d7a3e..7df0a5d 100644
--- a/logd/LogAudit.h
+++ b/logd/LogAudit.h
@@ -36,9 +36,6 @@
    public:
     LogAudit(LogBuffer* buf, LogReader* reader, int fdDmesg);
     int log(char* buf, size_t len);
-    bool isMonotonic() {
-        return logbuf->isMonotonic();
-    }
 
    protected:
     virtual bool onDataAvailable(SocketClient* cli);
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index a7323e8..2cb0c5e 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -50,48 +50,6 @@
             setSize(i, LOG_BUFFER_MIN_SIZE);
         }
     }
-    bool lastMonotonic = monotonic;
-    monotonic = android_log_clockid() == CLOCK_MONOTONIC;
-    if (lastMonotonic != monotonic) {
-        //
-        // Fixup all timestamps, may not be 100% accurate, but better than
-        // throwing what we have away when we get 'surprised' by a change.
-        // In-place element fixup so no need to check reader-lock. Entries
-        // should already be in timestamp order, but we could end up with a
-        // few out-of-order entries if new monotonics come in before we
-        // are notified of the reinit change in status. A Typical example would
-        // be:
-        //  --------- beginning of system
-        //      10.494082   184   201 D Cryptfs : Just triggered post_fs_data
-        //  --------- beginning of kernel
-        //       0.000000     0     0 I         : Initializing cgroup subsys
-        // as the act of mounting /data would trigger persist.logd.timestamp to
-        // be corrected. 1/30 corner case YMMV.
-        //
-        rdlock();
-        LogBufferElementCollection::iterator it = mLogElements.begin();
-        while ((it != mLogElements.end())) {
-            LogBufferElement* e = *it;
-            if (monotonic) {
-                if (!android::isMonotonic(e->mRealTime)) {
-                    LogKlog::convertRealToMonotonic(e->mRealTime);
-                    if ((e->mRealTime.tv_nsec % 1000) == 0) {
-                        e->mRealTime.tv_nsec++;
-                    }
-                }
-            } else {
-                if (android::isMonotonic(e->mRealTime)) {
-                    LogKlog::convertMonotonicToReal(e->mRealTime);
-                    if ((e->mRealTime.tv_nsec % 1000) == 0) {
-                        e->mRealTime.tv_nsec++;
-                    }
-                }
-            }
-            ++it;
-        }
-        unlock();
-    }
-
     // Release any sleeping reader threads to dump their current content.
     LogReaderThread::wrlock();
 
@@ -106,10 +64,7 @@
 }
 
 LogBuffer::LogBuffer(LastLogTimes* times, LogTags* tags, PruneList* prune)
-    : monotonic(android_log_clockid() == CLOCK_MONOTONIC),
-      mTimes(*times),
-      tags_(tags),
-      prune_(prune) {
+    : mTimes(*times), tags_(tags), prune_(prune) {
     pthread_rwlock_init(&mLogElementsLock, nullptr);
 
     log_id_for_each(i) {
diff --git a/logd/LogBuffer.h b/logd/LogBuffer.h
index eb41efb..3c45667 100644
--- a/logd/LogBuffer.h
+++ b/logd/LogBuffer.h
@@ -32,46 +32,6 @@
 #include "LogTags.h"
 #include "LogWhiteBlackList.h"
 
-//
-// We are either in 1970ish (MONOTONIC) or 2016+ish (REALTIME) so to
-// differentiate without prejudice, we use 1972 to delineate, earlier
-// is likely monotonic, later is real. Otherwise we start using a
-// dividing line between monotonic and realtime if more than a minute
-// difference between them.
-//
-namespace android {
-
-static bool isMonotonic(const log_time& mono) {
-    static const uint32_t EPOCH_PLUS_2_YEARS = 2 * 24 * 60 * 60 * 1461 / 4;
-    static const uint32_t EPOCH_PLUS_MINUTE = 60;
-
-    if (mono.tv_sec >= EPOCH_PLUS_2_YEARS) {
-        return false;
-    }
-
-    log_time now(CLOCK_REALTIME);
-
-    /* Timezone and ntp time setup? */
-    if (now.tv_sec >= EPOCH_PLUS_2_YEARS) {
-        return true;
-    }
-
-    /* no way to differentiate realtime from monotonic time */
-    if (now.tv_sec < EPOCH_PLUS_MINUTE) {
-        return false;
-    }
-
-    log_time cpu(CLOCK_MONOTONIC);
-    /* too close to call to differentiate monotonic times from realtime */
-    if ((cpu.tv_sec + EPOCH_PLUS_MINUTE) >= now.tv_sec) {
-        return false;
-    }
-
-    /* dividing line half way between monotonic and realtime */
-    return mono.tv_sec < ((cpu.tv_sec + now.tv_sec) / 2);
-}
-}
-
 typedef std::list<LogBufferElement*> LogBufferElementCollection;
 
 class LogBuffer {
@@ -91,8 +51,6 @@
 
     unsigned long mMaxSize[LOG_ID_MAX];
 
-    bool monotonic;
-
     LogBufferElement* lastLoggedElements[LOG_ID_MAX];
     LogBufferElement* droppedElements[LOG_ID_MAX];
     void log(LogBufferElement* elem);
@@ -103,9 +61,6 @@
     LogBuffer(LastLogTimes* times, LogTags* tags, PruneList* prune);
     ~LogBuffer();
     void init();
-    bool isMonotonic() {
-        return monotonic;
-    }
 
     int log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid, const char* msg,
             uint16_t len);
diff --git a/logd/LogKlog.cpp b/logd/LogKlog.cpp
index 5788ada..c308073 100644
--- a/logd/LogKlog.cpp
+++ b/logd/LogKlog.cpp
@@ -309,8 +309,6 @@
         }
         buf = cp;
 
-        if (isMonotonic()) return now;
-
         const char* b;
         if (((b = android::strnstr(cp, len, suspendStr))) &&
             (((b += strlen(suspendStr)) - cp) < len)) {
@@ -356,11 +354,7 @@
 
         convertMonotonicToReal(now);
     } else {
-        if (isMonotonic()) {
-            now = log_time(CLOCK_MONOTONIC);
-        } else {
-            now = log_time(CLOCK_REALTIME);
-        }
+        now = log_time(CLOCK_REALTIME);
     }
     return now;
 }
@@ -431,45 +425,6 @@
     return pri;
 }
 
-// Passed the entire SYSLOG_ACTION_READ_ALL buffer and interpret a
-// compensated start time.
-void LogKlog::synchronize(const char* buf, ssize_t len) {
-    const char* cp = android::strnstr(buf, len, suspendStr);
-    if (!cp) {
-        cp = android::strnstr(buf, len, resumeStr);
-        if (!cp) return;
-    } else {
-        const char* rp = android::strnstr(buf, len, resumeStr);
-        if (rp && (rp < cp)) cp = rp;
-    }
-
-    do {
-        --cp;
-    } while ((cp > buf) && (*cp != '\n'));
-    if (*cp == '\n') {
-        ++cp;
-    }
-    parseKernelPrio(cp, len - (cp - buf));
-
-    log_time now = sniffTime(cp, len - (cp - buf), true);
-
-    const char* suspended = android::strnstr(buf, len, suspendedStr);
-    if (!suspended || (suspended > cp)) {
-        return;
-    }
-    cp = suspended;
-
-    do {
-        --cp;
-    } while ((cp > buf) && (*cp != '\n'));
-    if (*cp == '\n') {
-        ++cp;
-    }
-    parseKernelPrio(cp, len - (cp - buf));
-
-    sniffTime(cp, len - (cp - buf), true);
-}
-
 // Convert kernel log priority number into an Android Logger priority number
 static int convertKernelPrioToAndroidPrio(int pri) {
     switch (pri & LOG_PRIMASK) {
@@ -789,7 +744,7 @@
     memcpy(np, p, b);
     np[b] = '\0';
 
-    if (!isMonotonic()) {
+    {
         // Watch out for singular race conditions with timezone causing near
         // integer quarter-hour jumps in the time and compensate accordingly.
         // Entries will be temporal within near_seconds * 2. b/21868540
diff --git a/logd/LogKlog.h b/logd/LogKlog.h
index 6bfd6a8..4c09751 100644
--- a/logd/LogKlog.h
+++ b/logd/LogKlog.h
@@ -42,17 +42,10 @@
     LogKlog(LogBuffer* buf, LogReader* reader, int fdWrite, int fdRead,
             bool auditd);
     int log(const char* buf, ssize_t len);
-    void synchronize(const char* buf, ssize_t len);
 
-    bool isMonotonic() {
-        return logbuf->isMonotonic();
-    }
     static void convertMonotonicToReal(log_time& real) {
         real += correction;
     }
-    static void convertRealToMonotonic(log_time& real) {
-        real -= correction;
-    }
 
    protected:
      log_time sniffTime(const char*& buf, ssize_t len, bool reverse);
diff --git a/logd/LogReader.cpp b/logd/LogReader.cpp
index 4702de5..a590cef 100644
--- a/logd/LogReader.cpp
+++ b/logd/LogReader.cpp
@@ -150,9 +150,8 @@
     // Convert realtime to sequence number
     if (start != log_time::EPOCH) {
         bool start_time_set = false;
-        bool is_monotonic = logbuf().isMonotonic() && android::isMonotonic(start);
         uint64_t last = sequence;
-        auto log_find_start = [pid, logMask, start, is_monotonic, &sequence, &start_time_set,
+        auto log_find_start = [pid, logMask, start, &sequence, &start_time_set,
                                &last](const LogBufferElement* element) -> int {
             if (pid && pid != element->getPid()) {
                 return 0;
@@ -164,15 +163,13 @@
                 sequence = element->getSequence();
                 start_time_set = true;
                 return -1;
-            } else if (!is_monotonic || android::isMonotonic(element->getRealTime())) {
+            } else {
                 if (start < element->getRealTime()) {
                     sequence = last;
                     start_time_set = true;
                     return -1;
                 }
                 last = element->getSequence();
-            } else {
-                last = element->getSequence();
             }
             return 0;
         };
diff --git a/logd/LogTags.cpp b/logd/LogTags.cpp
index 3e52b38..082e4a1 100644
--- a/logd/LogTags.cpp
+++ b/logd/LogTags.cpp
@@ -99,8 +99,7 @@
             struct tm tm;
             localtime_r(&now, &tm);
             char timebuf[20];
-            size_t len =
-                strftime(timebuf, sizeof(timebuf), "%Y-%m-%d %H:%M:%S", &tm);
+            strftime(timebuf, sizeof(timebuf), "%Y-%m-%d %H:%M:%S", &tm);
             android::base::WriteStringToFd(
                 android::base::StringPrintf(
                     "# Rebuilt %.20s, content owned by logd\n", timebuf),
@@ -189,7 +188,6 @@
 // Read the event log tags file, and build up our internal database
 void LogTags::ReadFileEventLogTags(const char* filename, bool warn) {
     bool etc = !strcmp(filename, system_event_log_tags);
-    bool debug = !etc && !strcmp(filename, debug_event_log_tags);
 
     if (!etc) {
         RebuildFileEventLogTags(filename, warn);
@@ -548,7 +546,7 @@
      */
 
     struct timespec ts;
-    clock_gettime(android_log_clockid(), &ts);
+    clock_gettime(CLOCK_REALTIME, &ts);
 
     android_log_header_t header = {
         .id = LOG_ID_EVENTS,
diff --git a/logd/README.property b/logd/README.property
index 1b7e165..6a9369a 100644
--- a/logd/README.property
+++ b/logd/README.property
@@ -44,10 +44,6 @@
                                          oldest entries of chattiest UID, and
                                          the chattiest PID of system
                                          (1000, or AID_SYSTEM).
-persist.logd.timestamp     string  ro    The recording timestamp source.
-                                         "m[onotonic]" is the only supported
-                                         key character, otherwise realtime.
-ro.logd.timestamp        string realtime default for persist.logd.timestamp
 log.tag                   string persist The global logging level, VERBOSE,
                                          DEBUG, INFO, WARN, ERROR, ASSERT or
                                          SILENT. Only the first character is
diff --git a/logd/main.cpp b/logd/main.cpp
index cc45eb3..d9dd249 100644
--- a/logd/main.cpp
+++ b/logd/main.cpp
@@ -109,21 +109,6 @@
     return 0;
 }
 
-// Property helper
-static bool check_flag(const char* prop, const char* flag) {
-    const char* cp = strcasestr(prop, flag);
-    if (!cp) {
-        return false;
-    }
-    // We only will document comma (,)
-    static const char sep[] = ",:;|+ \t\f";
-    if ((cp != prop) && !strchr(sep, cp[-1])) {
-        return false;
-    }
-    cp += strlen(flag);
-    return !*cp || !!strchr(sep, *cp);
-}
-
 static int fdDmesg = -1;
 void android::prdebug(const char* fmt, ...) {
     if (fdDmesg < 0) {
@@ -201,10 +186,6 @@
     }
     buf[--len] = '\0';
 
-    if (kl && kl->isMonotonic()) {
-        kl->synchronize(buf.get(), len);
-    }
-
     ssize_t sublen;
     for (char *ptr = nullptr, *tok = buf.get();
          (rc >= 0) && !!(tok = android::log_strntok_r(tok, len, ptr, sublen));
diff --git a/logd/tests/logd_test.cpp b/logd/tests/logd_test.cpp
index 1dd5c86..55737e9 100644
--- a/logd/tests/logd_test.cpp
+++ b/logd/tests/logd_test.cpp
@@ -606,7 +606,7 @@
     // A few tries to get it right just in case wrap kicks in due to
     // content providers being active during the test.
     int i = 5;
-    log_time start(android_log_clockid());
+    log_time start(CLOCK_REALTIME);
     start.tv_sec -= 30;  // reach back a moderate period of time
 
     while (--i) {
@@ -682,7 +682,7 @@
             if (msg > start) {
                 start = msg;
                 start.tv_sec += 30;
-                log_time now = log_time(android_log_clockid());
+                log_time now = log_time(CLOCK_REALTIME);
                 if (start > now) {
                     start = now;
                     --start.tv_sec;