Android 15.0.0 Release 6 (AP4A.241205.013)

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Merge tag 'android-15.0.0_r6' into staging/lineage-22.0_merge-android-15.0.0_r6

Android 15.0.0 Release 6 (AP4A.241205.013)

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# By Akilesh Kailash (13) and others
# Via Automerger Merge Worker (317) and others
* tag 'android-15.0.0_r6': (158 commits)
  trusty: storage: proxy: FS_READY property setting on vendor only
  Fix the trigger name for loading bpf programs.
  start netd earlier
  Replace base::RandInt with std::uniform_int_distribution
  trusty: keymint: rename trusty_ipc_dev property
  Move the `dist` target of `mke2fs` to `build/core/tasks`
  Remove define of SA_EXPOSE_TAGBITS.
  Add input event profile to mitigate input latency of input threads
  Remove usage of base/string/* in libfs_avb
  Add getFdStateDebug to access Looper's callbacks
  libsnapshot: CHECK -> CHECK_EQ
  Mount /mnt/vm earlier
  Define linker.config.json as a filegroup
  Remove usage of base/logging.h in libfs_avb
  debuggerd: recognize jumps to non-executable memory.
  Support vendor partition in non-debuggable pVMs
  Remind the reader that they'll need to modify CTS too.
  Rename system/core/rootdir/Android.mk to create_root_structure.mk
  trusty: keymint/gatekeeper: Pass device name from init scripts
  Remove unused variable.
  ...

 Conflicts:
	fs_mgr/libsnapshot/include/libsnapshot/snapshot.h
	fs_mgr/libsnapshot/snapshot.cpp
	init/Android.bp
	init/fuzzer/Android.bp

Change-Id: I29c07b3ac76940cb2b82726e98d2beb643b3e6e4

bootstat/bootstat.cpp

@@ -499,7 +499,7 @@ int32_t BootReasonStrToEnum(const std::string& boot_reason) {
 }
 
 // Canonical list of supported primary reboot reasons.
-const std::vector<const std::string> knownReasons = {
+const std::vector<std::string> knownReasons = {
     // clang-format off
     // kernel
     "watchdog",

debuggerd/Android.bp

@@ -359,6 +359,7 @@ cc_test {
         "libdebuggerd/test/dump_memory_test.cpp",
         "libdebuggerd/test/elf_fake.cpp",
         "libdebuggerd/test/log_fake.cpp",
+        "libdebuggerd/test/mte_stack_record_test.cpp",
         "libdebuggerd/test/open_files_list_test.cpp",
         "libdebuggerd/test/tombstone_proto_to_text_test.cpp",
     ],

debuggerd/client/debuggerd_client.cpp

@@ -138,7 +138,7 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
 
     auto remaining = end - std::chrono::steady_clock::now();
     if (remaining < decltype(remaining)::zero()) {
-      log_error(output_fd, 0, "timeout expired");
+      log_error(output_fd, 0, "timeout expired (update_timeout)");
       return false;
     }
 
@@ -254,7 +254,7 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
     if (timeout_ms <= 0) {
       remaining_ms = -1;
     } else if (remaining_ms < 0) {
-      log_error(output_fd, 0, "timeout expired");
+      log_error(output_fd, 0, "timeout expired before poll");
       return false;
     }
 
@@ -271,7 +271,7 @@ bool debuggerd_trigger_dump(pid_t tid, DebuggerdDumpType dump_type, unsigned int
         return false;
       }
     } else if (rc == 0) {
-      log_error(output_fd, 0, "timeout expired");
+      log_error(output_fd, 0, "poll timeout expired");
       return false;
     }
 

debuggerd/crash_dump.cpp

@@ -662,6 +662,15 @@ int main(int argc, char** argv) {
         info.pac_enabled_keys = -1;
       }
 
+#if defined(__aarch64__)
+      struct iovec tls_iov = {
+          &info.tls,
+          sizeof(info.tls),
+      };
+      if (ptrace(PTRACE_GETREGSET, thread, NT_ARM_TLS, reinterpret_cast<void*>(&tls_iov)) == -1) {
+        info.tls = 0;
+      }
+#endif
       if (thread == g_target_thread) {
         // Read the thread's registers along with the rest of the crash info out of the pipe.
         ReadCrashInfo(input_pipe, &siginfo, &info.registers, &process_info, &recoverable_crash);

debuggerd/debuggerd_test.cpp

@@ -18,6 +18,7 @@
 #include <dlfcn.h>
 #include <err.h>
 #include <fcntl.h>
+#include <inttypes.h>
 #include <linux/prctl.h>
 #include <malloc.h>
 #include <pthread.h>
@@ -69,7 +70,6 @@
 #include "crash_test.h"
 #include "debuggerd/handler.h"
 #include "gtest/gtest.h"
-#include "libdebuggerd/utility.h"
 #include "protocol.h"
 #include "tombstoned/tombstoned.h"
 #include "util.h"
@@ -741,6 +741,8 @@ TEST_F(CrasherTest, mte_multiple_causes) {
 }
 
 #if defined(__aarch64__)
+constexpr size_t kTagGranuleSize = 16;
+
 static uintptr_t CreateTagMapping() {
   // Some of the MTE tag dump tests assert that there is an inaccessible page to the left and right
   // of the PROT_MTE page, so map three pages and set the two guard pages to PROT_NONE.
@@ -1771,6 +1773,75 @@ TEST_F(CrasherTest, seccomp_crash_logcat) {
   AssertDeath(SIGABRT);
 }
 
+extern "C" void malloc_enable();
+extern "C" void malloc_disable();
+
+TEST_F(CrasherTest, seccomp_tombstone_no_allocation) {
+  int intercept_result;
+  unique_fd output_fd;
+
+  static const auto dump_type = kDebuggerdTombstone;
+  StartProcess(
+      []() {
+        std::thread a(foo);
+        std::thread b(bar);
+
+        std::this_thread::sleep_for(100ms);
+
+        // Disable allocations to verify that nothing in the fallback
+        // signal handler does an allocation.
+        malloc_disable();
+        raise_debugger_signal(dump_type);
+        _exit(0);
+      },
+      &seccomp_fork);
+
+  StartIntercept(&output_fd, dump_type);
+  FinishCrasher();
+  AssertDeath(0);
+  FinishIntercept(&intercept_result);
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+  ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
+  ASSERT_BACKTRACE_FRAME(result, "foo");
+  ASSERT_BACKTRACE_FRAME(result, "bar");
+}
+
+TEST_F(CrasherTest, seccomp_backtrace_no_allocation) {
+  int intercept_result;
+  unique_fd output_fd;
+
+  static const auto dump_type = kDebuggerdNativeBacktrace;
+  StartProcess(
+      []() {
+        std::thread a(foo);
+        std::thread b(bar);
+
+        std::this_thread::sleep_for(100ms);
+
+        // Disable allocations to verify that nothing in the fallback
+        // signal handler does an allocation.
+        malloc_disable();
+        raise_debugger_signal(dump_type);
+        _exit(0);
+      },
+      &seccomp_fork);
+
+  StartIntercept(&output_fd, dump_type);
+  FinishCrasher();
+  AssertDeath(0);
+  FinishIntercept(&intercept_result);
+  ASSERT_EQ(1, intercept_result) << "tombstoned reported failure";
+
+  std::string result;
+  ConsumeFd(std::move(output_fd), &result);
+  ASSERT_BACKTRACE_FRAME(result, "raise_debugger_signal");
+  ASSERT_BACKTRACE_FRAME(result, "foo");
+  ASSERT_BACKTRACE_FRAME(result, "bar");
+}
+
 TEST_F(CrasherTest, competing_tracer) {
   int intercept_result;
   unique_fd output_fd;

debuggerd/handler/debuggerd_fallback.cpp

@@ -48,50 +48,69 @@ using android::base::unique_fd;
 extern "C" bool __linker_enable_fallback_allocator();
 extern "C" void __linker_disable_fallback_allocator();
 
-// This is incredibly sketchy to do inside of a signal handler, especially when libbacktrace
+// This file implements a fallback path for processes that do not allow the
-// uses the C++ standard library throughout, but this code runs in the linker, so we'll be using
+// normal fork and exec of crash_dump to handle crashes/unwinds.
-// the linker's malloc instead of the libc one. Switch it out for a replacement, just in case.
+// The issue is that all of this happens from within a signal handler, which
-//
+// can cause problems since this code uses the linker allocator which is not
-// This isn't the default method of dumping because it can fail in cases such as address space
+// thread safe. In order to avoid any problems allocating, the code calls
-// exhaustion.
+// a function to switch to use a fallback allocator in the linker that will
+// only be used for the current thread. All of the libunwindstack code does
+// allocations using C++ stl, but should be fine since the code runs in the
+// linker and should use the fallback handler.
+
+// This method can still fail if the virtual space is exhausted on a 32 bit
+// process or mmap failing due to hitting the maximum number of maps (65535
+// total maps) on a 64 bit process.
+
+// Class to handle automatically turning on and off the fallback allocator.
+class ScopedUseFallbackAllocator {
+ public:
+  ScopedUseFallbackAllocator() { Enable(); }
+
+  ~ScopedUseFallbackAllocator() { Disable(); }
+
+  bool Enable() {
+    if (!enabled_) {
+      enabled_ = __linker_enable_fallback_allocator();
+      if (!enabled_) {
+        async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+                              "Unable to enable fallback allocator, already in use.");
+      }
+    }
+    return enabled_;
+  }
+
+  void Disable() {
+    if (enabled_) {
+      __linker_disable_fallback_allocator();
+      enabled_ = false;
+    }
+  }
+
+  bool enabled() { return enabled_; }
+
+ private:
+  bool enabled_ = false;
+};
+
 static void debuggerd_fallback_trace(int output_fd, ucontext_t* ucontext) {
-  if (!__linker_enable_fallback_allocator()) {
+  std::unique_ptr<unwindstack::Regs> regs;
-    async_safe_format_log(ANDROID_LOG_ERROR, "libc", "fallback allocator already in use");
-    return;
-  }
 
-  {
+  ThreadInfo thread;
-    std::unique_ptr<unwindstack::Regs> regs;
+  thread.pid = getpid();
+  thread.tid = gettid();
+  thread.thread_name = get_thread_name(gettid());
+  thread.registers.reset(
+      unwindstack::Regs::CreateFromUcontext(unwindstack::Regs::CurrentArch(), ucontext));
 
-    ThreadInfo thread;
+  // Do not use the thread cache here because it will call pthread_key_create
-    thread.pid = getpid();
+  // which doesn't work in linker code. See b/189803009.
-    thread.tid = gettid();
+  // Use a normal cached object because the thread is stopped, and there
-    thread.thread_name = get_thread_name(gettid());
+  // is no chance of data changing between reads.
-    thread.registers.reset(
+  auto process_memory = unwindstack::Memory::CreateProcessMemoryCached(getpid());
-        unwindstack::Regs::CreateFromUcontext(unwindstack::Regs::CurrentArch(), ucontext));
+  // TODO: Create this once and store it in a global?
-
+  unwindstack::AndroidLocalUnwinder unwinder(process_memory);
-    // Do not use the thread cache here because it will call pthread_key_create
+  dump_backtrace_thread(output_fd, &unwinder, thread);
-    // which doesn't work in linker code. See b/189803009.
-    // Use a normal cached object because the thread is stopped, and there
-    // is no chance of data changing between reads.
-    auto process_memory = unwindstack::Memory::CreateProcessMemoryCached(getpid());
-    // TODO: Create this once and store it in a global?
-    unwindstack::AndroidLocalUnwinder unwinder(process_memory);
-    dump_backtrace_thread(output_fd, &unwinder, thread);
-  }
-  __linker_disable_fallback_allocator();
-}
-
-static void debuggerd_fallback_tombstone(int output_fd, int proto_fd, ucontext_t* ucontext,
-                                         siginfo_t* siginfo, void* abort_message) {
-  if (!__linker_enable_fallback_allocator()) {
-    async_safe_format_log(ANDROID_LOG_ERROR, "libc", "fallback allocator already in use");
-    return;
-  }
-
-  engrave_tombstone_ucontext(output_fd, proto_fd, reinterpret_cast<uintptr_t>(abort_message),
-                             siginfo, ucontext);
-  __linker_disable_fallback_allocator();
 }
 
 static bool forward_output(int src_fd, int dst_fd, pid_t expected_tid) {
@@ -154,6 +173,11 @@ static std::pair<pid_t, int> unpack_thread_fd(uint64_t value) {
 }
 
 static void trace_handler(siginfo_t* info, ucontext_t* ucontext) {
+  ScopedUseFallbackAllocator allocator;
+  if (!allocator.enabled()) {
+    return;
+  }
+
   static std::atomic<uint64_t> trace_output(pack_thread_fd(-1, -1));
 
   if (info->si_value.sival_ptr == kDebuggerdFallbackSivalPtrRequestDump) {
@@ -181,6 +205,11 @@ static void trace_handler(siginfo_t* info, ucontext_t* ucontext) {
       async_safe_format_log(ANDROID_LOG_ERROR, "libc", "failed to write to output fd");
     }
 
+    // Stop using the fallback allocator before the close. This will prevent
+    // a race condition where the thread backtracing all of the threads tries
+    // to re-acquire the fallback allocator.
+    allocator.Disable();
+
     close(fd);
     return;
   }
@@ -210,10 +239,15 @@ static void trace_handler(siginfo_t* info, ucontext_t* ucontext) {
 
   // Send a signal to all of our siblings, asking them to dump their stack.
   pid_t current_tid = gettid();
-  if (!iterate_tids(current_tid, [&output_fd, &current_tid](pid_t tid) {
+  if (!iterate_tids(current_tid, [&allocator, &output_fd, &current_tid](pid_t tid) {
         if (current_tid == tid) {
           return;
         }
+
+        if (!allocator.enabled()) {
+          return;
+        }
+
         // Use a pipe, to be able to detect situations where the thread gracefully exits before
         // receiving our signal.
         unique_fd pipe_read, pipe_write;
@@ -233,22 +267,29 @@ static void trace_handler(siginfo_t* info, ucontext_t* ucontext) {
           return;
         }
 
+        // Disable our use of the fallback allocator while the target thread
+        // is getting the backtrace.
+        allocator.Disable();
+
         siginfo_t siginfo = {};
         siginfo.si_code = SI_QUEUE;
         siginfo.si_value.sival_ptr = kDebuggerdFallbackSivalPtrRequestDump;
         siginfo.si_pid = getpid();
         siginfo.si_uid = getuid();
 
-        if (syscall(__NR_rt_tgsigqueueinfo, getpid(), tid, BIONIC_SIGNAL_DEBUGGER, &siginfo) != 0) {
+        if (syscall(__NR_rt_tgsigqueueinfo, getpid(), tid, BIONIC_SIGNAL_DEBUGGER, &siginfo) == 0) {
+          if (!forward_output(pipe_read.get(), output_fd.get(), tid)) {
+            async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+                                  "timeout expired while waiting for thread %d to dump", tid);
+          }
+        } else {
           async_safe_format_log(ANDROID_LOG_ERROR, "libc", "failed to send trace signal to %d: %s",
                                 tid, strerror(errno));
-          return;
         }
 
-        bool success = forward_output(pipe_read.get(), output_fd.get(), tid);
+        // The thread should be finished now, so try and re-enable the fallback allocator.
-        if (!success) {
+        if (!allocator.Enable()) {
-          async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+          return;
-                                "timeout expired while waiting for thread %d to dump", tid);
         }
 
         // Regardless of whether the poll succeeds, check to see if the thread took fd ownership.
@@ -260,14 +301,15 @@ static void trace_handler(siginfo_t* info, ucontext_t* ucontext) {
             close(fd);
           }
         }
-
-        return;
       })) {
     async_safe_format_log(ANDROID_LOG_ERROR, "libc", "failed to open /proc/%d/task: %s",
                           current_tid, strerror(errno));
   }
 
-  dump_backtrace_footer(output_fd.get());
+  if (allocator.enabled()) {
+    dump_backtrace_footer(output_fd.get());
+  }
+
   tombstoned_notify_completion(tombstone_socket.get());
 }
 
@@ -295,7 +337,13 @@ static void crash_handler(siginfo_t* info, ucontext_t* ucontext, void* abort_mes
   unique_fd tombstone_socket, output_fd, proto_fd;
   bool tombstoned_connected = tombstoned_connect(getpid(), &tombstone_socket, &output_fd, &proto_fd,
                                                  kDebuggerdTombstoneProto);
-  debuggerd_fallback_tombstone(output_fd.get(), proto_fd.get(), ucontext, info, abort_message);
+  {
+    ScopedUseFallbackAllocator allocator;
+    if (allocator.enabled()) {
+      engrave_tombstone_ucontext(output_fd.get(), proto_fd.get(),
+                                 reinterpret_cast<uintptr_t>(abort_message), info, ucontext);
+    }
+  }
   if (tombstoned_connected) {
     tombstoned_notify_completion(tombstone_socket.get());
   }

debuggerd/handler/debuggerd_handler.cpp

@@ -36,10 +36,12 @@
 #include <sys/uio.h>
 #include <sys/un.h>
 #include <sys/wait.h>
+#include <time.h>
 #include <unistd.h>
 
 #include <android-base/macros.h>
 #include <android-base/parsebool.h>
+#include <android-base/parseint.h>
 #include <android-base/properties.h>
 #include <android-base/unique_fd.h>
 #include <async_safe/log.h>
@@ -115,6 +117,59 @@ static bool is_permissive_mte() {
          (permissive_env && ParseBool(permissive_env) == ParseBoolResult::kTrue);
 }
 
+static bool parse_uint_with_error_reporting(const char* s, const char* name, int* v) {
+  if (android::base::ParseInt(s, v) && *v >= 0) {
+    return true;
+  }
+  async_safe_format_log(ANDROID_LOG_ERROR, "libc", "invalid %s: %s", name, s);
+  return false;
+}
+
+// We cannot use base::GetIntProperty, because that internally uses
+// std::string, which allocates.
+static bool property_parse_int(const char* name, int* out) {
+  const prop_info* pi = __system_property_find(name);
+  if (!pi) return false;
+  struct cookie_t {
+    int* out;
+    bool empty;
+  } cookie{out, true};
+  __system_property_read_callback(
+      pi,
+      [](void* raw_cookie, const char* name, const char* value, uint32_t) {
+        // Property is set to empty value, ignoring.
+        if (!*value) return;
+        cookie_t* cookie = reinterpret_cast<cookie_t*>(raw_cookie);
+        if (parse_uint_with_error_reporting(value, name, cookie->out)) cookie->empty = false;
+      },
+      &cookie);
+  return !cookie.empty;
+}
+
+static int permissive_mte_renable_timer() {
+  if (char* env = getenv("MTE_PERMISSIVE_REENABLE_TIME_CPUMS")) {
+    int v;
+    if (parse_uint_with_error_reporting(env, "MTE_PERMISSIVE_REENABLE_TIME_CPUMS", &v)) return v;
+  }
+
+  char process_sysprop_name[512];
+  async_safe_format_buffer(process_sysprop_name, sizeof(process_sysprop_name),
+                           "persist.sys.mte.permissive_reenable_timer.process.%s", getprogname());
+  int v;
+  if (property_parse_int(process_sysprop_name, &v)) return v;
+  if (property_parse_int("persist.sys.mte.permissive_reenable_timer.default", &v)) return v;
+  char process_deviceconf_sysprop_name[512];
+  async_safe_format_buffer(
+      process_deviceconf_sysprop_name, sizeof(process_deviceconf_sysprop_name),
+      "persist.device_config.memory_safety_native.permissive_reenable_timer.process.%s",
+      getprogname());
+  if (property_parse_int(process_deviceconf_sysprop_name, &v)) return v;
+  if (property_parse_int(
+          "persist.device_config.memory_safety_native.permissive_reenable_timer.default", &v))
+    return v;
+  return 0;
+}
+
 static inline void futex_wait(volatile void* ftx, int value) {
   syscall(__NR_futex, ftx, FUTEX_WAIT, value, nullptr, nullptr, 0);
 }
@@ -599,12 +654,40 @@ static void debuggerd_signal_handler(int signal_number, siginfo_t* info, void* c
     if (tagged_addr_ctrl < 0) {
       fatal_errno("failed to PR_GET_TAGGED_ADDR_CTRL");
     }
+    int previous = tagged_addr_ctrl & PR_MTE_TCF_MASK;
     tagged_addr_ctrl = (tagged_addr_ctrl & ~PR_MTE_TCF_MASK) | PR_MTE_TCF_NONE;
     if (prctl(PR_SET_TAGGED_ADDR_CTRL, tagged_addr_ctrl, 0, 0, 0) < 0) {
       fatal_errno("failed to PR_SET_TAGGED_ADDR_CTRL");
     }
-    async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+    if (int reenable_timer = permissive_mte_renable_timer()) {
-                          "MTE ERROR DETECTED BUT RUNNING IN PERMISSIVE MODE. CONTINUING.");
+      async_safe_format_log(ANDROID_LOG_ERROR, "libc",
+                            "MTE ERROR DETECTED BUT RUNNING IN PERMISSIVE MODE. CONTINUING WITH "
+                            "MTE DISABLED FOR %d MS OF CPU TIME.",
+                            reenable_timer);
+      timer_t timerid{};
+      struct sigevent sev {};
+      sev.sigev_signo = BIONIC_ENABLE_MTE;
+      sev.sigev_notify = SIGEV_THREAD_ID;
+      sev.sigev_value.sival_int = previous;
+      sev.sigev_notify_thread_id = __gettid();
+      // This MUST be CLOCK_THREAD_CPUTIME_ID. If we used CLOCK_MONOTONIC we could get stuck
+      // in an endless loop of re-running the same instruction, calling this signal handler,
+      // and re-enabling MTE before we had a chance to re-run the instruction.
+      if (timer_create(CLOCK_THREAD_CPUTIME_ID, &sev, &timerid) == -1) {
+        fatal_errno("timer_create() failed");
+      }
+      struct itimerspec its {};
+      its.it_value.tv_sec = reenable_timer / 1000;
+      its.it_value.tv_nsec = (reenable_timer % 1000) * 1000000;
+
+      if (timer_settime(timerid, 0, &its, nullptr) == -1) {
+        fatal_errno("timer_settime() failed");
+      }
+    } else {
+      async_safe_format_log(
+          ANDROID_LOG_ERROR, "libc",
+          "MTE ERROR DETECTED BUT RUNNING IN PERMISSIVE MODE. CONTINUING WITH MTE DISABLED.");
+    }
     pthread_mutex_unlock(&crash_mutex);
   }
 
@@ -755,7 +838,6 @@ void debuggerd_init(debuggerd_callbacks_t* callbacks) {
   // Use the alternate signal stack if available so we can catch stack overflows.
   action.sa_flags |= SA_ONSTACK;
 
-#define SA_EXPOSE_TAGBITS 0x00000800
   // Request that the kernel set tag bits in the fault address. This is necessary for diagnosing MTE
   // faults.
   action.sa_flags |= SA_EXPOSE_TAGBITS;

debuggerd/libdebuggerd/include/libdebuggerd/tombstone.h

@@ -73,5 +73,8 @@ bool tombstone_proto_to_text(
 
 void fill_in_backtrace_frame(BacktraceFrame* f, const unwindstack::FrameData& frame);
 void set_human_readable_cause(Cause* cause, uint64_t fault_addr);
-
+#if defined(__aarch64__)
+void dump_stack_history(unwindstack::AndroidUnwinder* unwinder, uintptr_t target_tls,
+                        StackHistoryBuffer& shb_ob, bool nounwind = false);
+#endif
 #endif  // _DEBUGGERD_TOMBSTONE_H

debuggerd/libdebuggerd/include/libdebuggerd/types.h

@@ -41,6 +41,9 @@ struct ThreadInfo {
   siginfo_t* siginfo = nullptr;
 
   std::unique_ptr<unwindstack::Regs> guest_registers;
+#if defined(__aarch64__)
+  uintptr_t tls;  // This is currently used for MTE stack history buffer.
+#endif
 };
 
 // This struct is written into a pipe from inside the crashing process.

debuggerd/libdebuggerd/test/host_signal_fixup.h

@@ -1,65 +0,0 @@
-/*
- * 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 _DEBUGGERD_TEST_HOST_SIGNAL_FIXUP_H
-#define _DEBUGGERD_TEST_HOST_SIGNAL_FIXUP_H
-
-#include <signal.h>
-
-#if !defined(__BIONIC__)
-
-// In order to compile parts of debuggerd for the host, we need to
-// define these values.
-
-#if !defined(NSIGILL)
-#define NSIGILL ILL_BADSTK
-#endif
-
-#if !defined(BUS_MCEERR_AR)
-#define BUS_MCEERR_AR 4
-#endif
-#if !defined(BUS_MCEERR_AO)
-#define BUS_MCEERR_AO 5
-#endif
-#if !defined(NSIGBUS)
-#define NSIGBUS BUS_MCEERR_AO
-#endif
-
-#if !defined(NSIGFPE)
-#define NSIGFPE FPE_FLTSUB
-#endif
-
-#if !defined(NSIGSEGV)
-#define NSIGSEGV SEGV_ACCERR
-#endif
-
-#if !defined(TRAP_BRANCH)
-#define TRAP_BRANCH 3
-#endif
-#if !defined(TRAP_HWBKPT)
-#define TRAP_HWBKPT 4
-#endif
-#if !defined(NSIGTRAP)
-#define NSIGTRAP TRAP_HWBKPT
-#endif
-
-#if !defined(SI_DETHREAD)
-#define SI_DETHREAD (-7)
-#endif
-
-#endif
-
-#endif // _DEBUGGERD_TEST_HOST_SIGNAL_FIXUP_H

debuggerd/libdebuggerd/test/mte_stack_record_test.cpp

@@ -0,0 +1,157 @@
+/*
+ * Copyright (C) 2024 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.
+ */
+#if defined(__aarch64__)
+
+#include <stdint.h>
+#include <sys/mman.h>
+
+#include <optional>
+
+#include "bionic/mte.h"
+#include "bionic/page.h"
+#include "unwindstack/AndroidUnwinder.h"
+#include "unwindstack/Memory.h"
+
+#include <android-base/test_utils.h>
+#include "gtest/gtest.h"
+
+#include "libdebuggerd/tombstone.h"
+
+struct ScopedUnmap {
+  void* ptr;
+  size_t size;
+  ~ScopedUnmap() { munmap(ptr, size); }
+};
+
+class MteStackHistoryTest : public ::testing::TestWithParam<int> {
+  void SetUp() override {
+#if !defined(__aarch64__)
+    GTEST_SKIP();
+#endif
+    SKIP_WITH_HWASAN;
+    unwinder.emplace();
+    unwindstack::ErrorData E;
+    ASSERT_TRUE(unwinder->Initialize(E));
+  }
+
+ protected:
+  // std::optional so we don't construct it for the SKIP cases.
+  std::optional<unwindstack::AndroidLocalUnwinder> unwinder;
+};
+
+TEST(MteStackHistoryUnwindTest, TestOne) {
+#if !defined(__aarch64__)
+  GTEST_SKIP();
+#endif
+  SKIP_WITH_HWASAN;
+  size_t size = stack_mte_ringbuffer_size(0);
+  char* data = static_cast<char*>(stack_mte_ringbuffer_allocate(0, nullptr));
+  ScopedUnmap s{data, size};
+
+  uintptr_t taggedfp = (1ULL << 56) | 1;
+  uintptr_t pc = reinterpret_cast<uintptr_t>(&memcpy);
+  memcpy(data, &pc, sizeof(pc));
+  memcpy(data + 8, &taggedfp, sizeof(taggedfp));
+
+  // The MTE TLS is at TLS - 3, so we allocate 3 placeholders.
+  void* tls[4] = {data + 16};
+
+  unwindstack::AndroidLocalUnwinder unwinder;
+  unwindstack::ErrorData E;
+  unwinder.Initialize(E);
+  StackHistoryBuffer shb;
+  dump_stack_history(&unwinder, reinterpret_cast<uintptr_t>(&tls[3]), shb, /* nounwind= */ false);
+  ASSERT_EQ(shb.entries_size(), 1);
+  const StackHistoryBufferEntry& e = shb.entries(0);
+  EXPECT_EQ(e.addr().pc(), pc);
+  EXPECT_EQ(e.addr().file_name(), "/apex/com.android.runtime/lib64/bionic/libc.so");
+  EXPECT_EQ(e.fp(), 1ULL);
+  EXPECT_EQ(e.tag(), 1ULL);
+}
+
+TEST_P(MteStackHistoryTest, TestEmpty) {
+  int size_cls = GetParam();
+  size_t size = stack_mte_ringbuffer_size(size_cls);
+  void* data = stack_mte_ringbuffer_allocate(size_cls, nullptr);
+  ScopedUnmap s{data, size};
+  // The MTE TLS is at TLS - 3, so we allocate 3 placeholders.
+  void* tls[4] = {data};
+
+  StackHistoryBuffer shb;
+  dump_stack_history(&*unwinder, reinterpret_cast<uintptr_t>(&tls[3]), shb, /* nounwind= */ true);
+  EXPECT_EQ(shb.entries_size(), 0);
+}
+
+TEST_P(MteStackHistoryTest, TestFull) {
+  int size_cls = GetParam();
+  size_t size = stack_mte_ringbuffer_size(size_cls);
+  char* data = static_cast<char*>(stack_mte_ringbuffer_allocate(size_cls, nullptr));
+  ScopedUnmap s{data, size};
+  uintptr_t itr = 1;
+  for (char* d = data; d < &data[size]; d += 16) {
+    uintptr_t taggedfp = ((itr & 15) << 56) | itr;
+    uintptr_t pc = itr;
+    memcpy(d, &pc, sizeof(pc));
+    memcpy(d + 8, &taggedfp, sizeof(taggedfp));
+    ++itr;
+  }
+  // The MTE TLS is at TLS - 3, so we allocate 3 placeholders.
+  // Because the buffer is full, and we point at one past the last inserted element,
+  // due to wrap-around we point at the beginning of the buffer.
+  void* tls[4] = {data};
+
+  StackHistoryBuffer shb;
+  dump_stack_history(&*unwinder, reinterpret_cast<uintptr_t>(&tls[3]), shb, /* nounwind= */ true);
+  EXPECT_EQ(static_cast<size_t>(shb.entries_size()), size / 16);
+  for (const auto& entry : shb.entries()) {
+    EXPECT_EQ(entry.addr().pc(), --itr);
+    EXPECT_EQ(entry.addr().pc(), entry.fp());
+    EXPECT_EQ(entry.addr().pc() & 15, entry.tag());
+  }
+}
+
+TEST_P(MteStackHistoryTest, TestHalfFull) {
+  int size_cls = GetParam();
+  size_t size = stack_mte_ringbuffer_size(size_cls);
+  size_t half_size = size / 2;
+
+  char* data = static_cast<char*>(stack_mte_ringbuffer_allocate(size_cls, nullptr));
+  ScopedUnmap s{data, size};
+
+  uintptr_t itr = 1;
+  for (char* d = data; d < &data[half_size]; d += 16) {
+    uintptr_t taggedfp = ((itr & 15) << 56) | itr;
+    uintptr_t pc = itr;
+    memcpy(d, &pc, sizeof(pc));
+    memcpy(d + 8, &taggedfp, sizeof(taggedfp));
+    ++itr;
+  }
+  // The MTE TLS is at TLS - 3, so we allocate 3 placeholders.
+  void* tls[4] = {&data[half_size]};
+
+  StackHistoryBuffer shb;
+  dump_stack_history(&*unwinder, reinterpret_cast<uintptr_t>(&tls[3]), shb, /* nounwind= */ true);
+  EXPECT_EQ(static_cast<size_t>(shb.entries_size()), half_size / 16);
+  for (const auto& entry : shb.entries()) {
+    EXPECT_EQ(entry.addr().pc(), --itr);
+    EXPECT_EQ(entry.addr().pc(), entry.fp());
+    EXPECT_EQ(entry.addr().pc() & 15, entry.tag());
+  }
+}
+
+INSTANTIATE_TEST_SUITE_P(MteStackHistoryTestInstance, MteStackHistoryTest, testing::Range(0, 8));
+
+#endif

debuggerd/libdebuggerd/test/tombstone_proto_to_text_test.cpp

@@ -134,3 +134,31 @@ TEST_F(TombstoneProtoToTextTest, crash_detail_bytes) {
   ProtoToString();
   EXPECT_MATCH(text_, R"(CRASH_DETAIL_NAME: 'helloworld\\1\\255\\3')");
 }
+
+TEST_F(TombstoneProtoToTextTest, stack_record) {
+  auto* cause = tombstone_->add_causes();
+  cause->set_human_readable("stack tag-mismatch on thread 123");
+  auto* stack = tombstone_->mutable_stack_history_buffer();
+  stack->set_tid(123);
+  {
+    auto* shb_entry = stack->add_entries();
+    shb_entry->set_fp(0x1);
+    shb_entry->set_tag(0xb);
+    auto* addr = shb_entry->mutable_addr();
+    addr->set_rel_pc(0x567);
+    addr->set_file_name("foo.so");
+    addr->set_build_id("ABC123");
+  }
+  {
+    auto* shb_entry = stack->add_entries();
+    shb_entry->set_fp(0x2);
+    shb_entry->set_tag(0xc);
+    auto* addr = shb_entry->mutable_addr();
+    addr->set_rel_pc(0x678);
+    addr->set_file_name("bar.so");
+  }
+  ProtoToString();
+  EXPECT_MATCH(text_, "stack tag-mismatch on thread 123");
+  EXPECT_MATCH(text_, "stack_record fp:0x1 tag:0xb pc:foo\\.so\\+0x567 \\(BuildId: ABC123\\)");
+  EXPECT_MATCH(text_, "stack_record fp:0x2 tag:0xc pc:bar\\.so\\+0x678");
+}

debuggerd/libdebuggerd/tombstone_proto.cpp

@@ -27,6 +27,7 @@
 #include <inttypes.h>
 #include <signal.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
@@ -49,9 +50,11 @@
 
 #include <android/log.h>
 #include <android/set_abort_message.h>
-#include <bionic/macros.h>
-#include <bionic/reserved_signals.h>
 #include <bionic/crash_detail_internal.h>
+#include <bionic/macros.h>
+#include <bionic/mte.h>
+#include <bionic/reserved_signals.h>
+#include <bionic/tls_defines.h>
 #include <log/log.h>
 #include <log/log_read.h>
 #include <log/logprint.h>
@@ -202,8 +205,117 @@ void set_human_readable_cause(Cause* cause, uint64_t fault_addr) {
       error_type_str, diff, byte_suffix, location_str, heap_object.size(), heap_object.address()));
 }
 
+#if defined(__aarch64__)
+void dump_stack_history(unwindstack::AndroidUnwinder* unwinder, uintptr_t target_tls,
+                        StackHistoryBuffer& shb_obj, bool nounwind) {
+  auto process_memory = unwinder->GetProcessMemory();
+  target_tls += sizeof(void*) * TLS_SLOT_STACK_MTE;
+  uintptr_t stack_mte;
+  if (!process_memory->ReadFully(target_tls, &stack_mte, sizeof(stack_mte))) {
+    async_safe_format_log(ANDROID_LOG_ERROR, LOG_TAG,
+                          "dump_stack_history: failed to read TLS_SLOT_STACK_MTE: %m");
+    return;
+  }
+  if (stack_mte == 0) {
+    async_safe_format_log(ANDROID_LOG_DEBUG, LOG_TAG,
+                          "dump_stack_history: stack history buffer is null");
+    return;
+  }
+  uintptr_t untagged_stack_mte = untag_address(stack_mte);
+  uintptr_t buf_size = stack_mte_ringbuffer_size_from_pointer(stack_mte);
+  if (buf_size == 0) {
+    async_safe_format_log(ANDROID_LOG_ERROR, LOG_TAG, "dump_stack_history: empty size");
+    return;
+  }
+  uintptr_t buf_start = untagged_stack_mte & ~(buf_size - 1ULL);
+  std::vector<char> buf(buf_size);
+  if (!process_memory->ReadFully(buf_start, buf.data(), buf.size())) {
+    async_safe_format_log(ANDROID_LOG_ERROR, LOG_TAG,
+                          "dump_stack_history: failed to read stack history: %m");
+    return;
+  }
+  uintptr_t original_off = untagged_stack_mte - buf_start;
+  if (original_off % 16 || original_off > buf_size) {
+    async_safe_format_log(ANDROID_LOG_ERROR, LOG_TAG,
+                          "dump_stack_history: invalid offset: %" PRIuPTR, original_off);
+    return;
+  }
+
+  // The original_off is the next slot that would have been written, so the last
+  // slot that was written is the previous one.
+  for (uintptr_t idx = 16; idx <= buf_size; idx += 16) {
+    int64_t off = original_off - idx;
+    if (off < 0) off += buf_size;
+    uintptr_t pc, taggedfp;
+    memcpy(&pc, &(buf[off]), sizeof(pc));
+    memcpy(&taggedfp, &(buf[off + sizeof(pc)]), sizeof(taggedfp));
+
+    if (pc == 0) break;
+    uintptr_t fp = untag_address(taggedfp);
+    uintptr_t tag = taggedfp >> 56;
+
+    unwindstack::FrameData frame_data;
+
+    if (nounwind) {
+      frame_data.pc = pc;
+    } else {
+      // +4 is to counteract the "pc adjustment" in BuildFrameFromPcOnly.
+      // BuildFrameFromPcOnly assumes we are unwinding, so it needs to correct for that
+      // the PC is the return address. That is not the case here.
+      // It doesn't really matter, because either should be in the correct function, but
+      // this is more correct (and consistent with the nounwind case).
+      frame_data = unwinder->BuildFrameFromPcOnly(pc);
+      frame_data.pc += 4;
+      frame_data.rel_pc += 4;
+    }
+
+    StackHistoryBufferEntry* entry = shb_obj.add_entries();
+    fill_in_backtrace_frame(entry->mutable_addr(), frame_data);
+    entry->set_fp(fp);
+    entry->set_tag(tag);
+  }
+}
+
+static pid_t get_containing_thread(unwindstack::MapInfo* map_info, pid_t main_tid) {
+  if (map_info == nullptr) return 0;
+
+  std::string name = map_info->name();
+  if (name == "[stack]") {
+    return main_tid;
+  }
+  int tid;
+  if (sscanf(name.c_str(), "[anon:stack_and_tls:%d", &tid) != 1) {
+    return 0;
+  }
+  return tid;
+}
+
+static std::optional<std::string> maybe_stack_mte_cause(
+    Tombstone* tombstone, unwindstack::AndroidUnwinder* unwinder, const ThreadInfo& target_thread,
+    [[maybe_unused]] const std::map<pid_t, ThreadInfo>& threads, uint64_t fault_addr) {
+  unwindstack::Maps* maps = unwinder->GetMaps();
+  auto map_info = maps->Find(untag_address(fault_addr));
+  pid_t tid = get_containing_thread(map_info.get(), target_thread.tid);
+  if (!tid) {
+    return std::nullopt;
+  }
+  auto it = threads.find(tid);
+  if (it != threads.end()) {
+    StackHistoryBuffer* shb = tombstone->mutable_stack_history_buffer();
+    shb->set_tid(tid);
+    dump_stack_history(unwinder, it->second.tls, *shb);
+  } else {
+    async_safe_format_log(ANDROID_LOG_ERROR, LOG_TAG,
+                          "dump_probable_cause: unknown target thread %d", tid);
+  }
+  return StringPrintf("stack tag-mismatch on thread %u", tid);
+}
+
+#endif
+
 static void dump_probable_cause(Tombstone* tombstone, unwindstack::AndroidUnwinder* unwinder,
-                                const ProcessInfo& process_info, const ThreadInfo& target_thread) {
+                                const ProcessInfo& process_info, const ThreadInfo& target_thread,
+                                [[maybe_unused]] const std::map<pid_t, ThreadInfo>& threads) {
 #if defined(USE_SCUDO)
   ScudoCrashData scudo_crash_data(unwinder->GetProcessMemory().get(), process_info);
   if (scudo_crash_data.CrashIsMine()) {
@@ -244,10 +356,21 @@ static void dump_probable_cause(Tombstone* tombstone, unwindstack::AndroidUnwind
     auto map_info = maps->Find(fault_addr);
     if (map_info != nullptr && map_info->flags() == PROT_EXEC) {
       cause = "execute-only (no-read) memory access error; likely due to data in .text.";
+    } else if (fault_addr == target_thread.registers->pc() &&
+               map_info != nullptr && (map_info->flags() & PROT_EXEC) == 0) {
+      cause = "trying to execute non-executable memory.";
     } else {
       cause = get_stack_overflow_cause(fault_addr, target_thread.registers->sp(), maps);
     }
-  } else if (si->si_signo == SIGSYS && si->si_code == SYS_SECCOMP) {
+  }
+#if defined(__aarch64__) && defined(SEGV_MTESERR)
+  else if (si->si_signo == SIGSEGV && si->si_code == SEGV_MTESERR) {
+    // If this was a heap MTE crash, it would have been handled by scudo. Checking whether it
+    // is a stack one.
+    cause = maybe_stack_mte_cause(tombstone, unwinder, target_thread, threads, fault_addr);
+  }
+#endif
+  else if (si->si_signo == SIGSYS && si->si_code == SYS_SECCOMP) {
     cause = StringPrintf("seccomp prevented call to disallowed %s system call %d", ABI_STRING,
                          si->si_syscall);
   }
@@ -788,7 +911,7 @@ void engrave_tombstone_proto(Tombstone* tombstone, unwindstack::AndroidUnwinder*
     }
   }
 
-  dump_probable_cause(&result, unwinder, process_info, target_thread);
+  dump_probable_cause(&result, unwinder, process_info, target_thread, threads);
 
   dump_mappings(&result, unwinder->GetMaps(), unwinder->GetProcessMemory());
 

debuggerd/libdebuggerd/tombstone_proto_to_text.cpp

@@ -511,6 +511,19 @@ static void print_main_thread(CallbackType callback, const Tombstone& tombstone,
         "order of likelihood.");
   }
 
+  if (tombstone.has_stack_history_buffer()) {
+    for (const StackHistoryBufferEntry& shbe : tombstone.stack_history_buffer().entries()) {
+      std::string stack_record_str = StringPrintf(
+          "stack_record fp:0x%" PRIx64 " tag:0x%" PRIx64 " pc:%s+0x%" PRIx64, shbe.fp(), shbe.tag(),
+          shbe.addr().file_name().c_str(), shbe.addr().rel_pc());
+      if (!shbe.addr().build_id().empty()) {
+        StringAppendF(&stack_record_str, " (BuildId: %s)", shbe.addr().build_id().c_str());
+      }
+
+      CBL("%s", stack_record_str.c_str());
+    }
+  }
+
   for (const Cause& cause : tombstone.causes()) {
     if (tombstone.causes_size() > 1) {
       CBS("");

debuggerd/proto/tombstone.proto

@@ -22,6 +22,21 @@ message CrashDetail {
   reserved 3 to 999;
 }
 
+message StackHistoryBufferEntry {
+  BacktraceFrame addr = 1;
+  uint64 fp = 2;
+  uint64 tag = 3;
+
+  reserved 4 to 999;
+}
+
+message StackHistoryBuffer {
+  uint64 tid = 1;
+  repeated StackHistoryBufferEntry entries = 2;
+
+  reserved 3 to 999;
+}
+
 message Tombstone {
   Architecture arch = 1;
   Architecture guest_arch = 24;
@@ -54,7 +69,9 @@ message Tombstone {
   uint32 page_size = 22;
   bool has_been_16kb_mode = 23;
 
-  reserved 26 to 999;
+  StackHistoryBuffer stack_history_buffer = 26;
+
+  reserved 27 to 999;
 }
 
 enum Architecture {

debuggerd/test_permissive_mte/mte_crash.cpp

@@ -20,5 +20,14 @@
 int main(int, char**) {
   volatile char* f = (char*)malloc(1);
   printf("%c\n", f[17]);
+#ifdef __aarch64__
+  if (getenv("MTE_PERMISSIVE_REENABLE_TIME_CPUMS")) {
+    // Burn some cycles because the MTE_PERMISSIVE_REENABLE_TIME_CPUMS is based on CPU clock.
+    for (int i = 0; i < 1000000000; ++i) {
+      asm("isb");
+    }
+    printf("%c\n", f[17]);
+  }
+#endif
   return 0;
 }

debuggerd/test_permissive_mte/src/com/android/tests/debuggerd/PermissiveMteTest.java

@@ -97,6 +97,34 @@ public class PermissiveMteTest extends BaseHostJUnit4Test {
     }
     assertThat(numberTombstones).isEqualTo(1);
   }
+
+  @Test
+  public void testReenableCrash() throws Exception {
+    CommandResult result =
+        getDevice().executeShellV2Command("MTE_PERMISSIVE=1 MTE_PERMISSIVE_REENABLE_TIME_CPUMS=1 "
+                                          + "/data/local/tmp/mte_crash testReenableCrash "
+                                          + mUUID);
+    assertThat(result.getExitCode()).isEqualTo(0);
+    int numberTombstones = 0;
+    String[] tombstones = getDevice().getChildren("/data/tombstones");
+    for (String tombstone : tombstones) {
+      if (!tombstone.endsWith(".pb")) {
+        continue;
+      }
+      String tombstonePath = "/data/tombstones/" + tombstone;
+      Tombstone tombstoneProto = parseTombstone(tombstonePath);
+      if (!tombstoneProto.getCommandLineList().stream().anyMatch(x -> x.contains(mUUID))) {
+        continue;
+      }
+      if (!tombstoneProto.getCommandLineList().stream().anyMatch(
+              x -> x.contains("testReenableCrash"))) {
+        continue;
+      }
+      numberTombstones++;
+    }
+    assertThat(numberTombstones).isEqualTo(2);
+  }
+
   @Test
   public void testCrashProperty() throws Exception {
     String prevValue = getDevice().getProperty("persist.sys.mte.permissive");

debuggerd/tombstoned/tombstoned.cpp

@@ -158,7 +158,7 @@ class CrashQueue {
       }
     }
 
-    return std::move(result);
+    return result;
   }
 
   std::optional<CrashOutput> get_output(DebuggerdDumpType dump_type) {

fastboot/Android.bp

@@ -186,6 +186,7 @@ cc_binary {
         "libprotobuf-cpp-lite",
         "libsparse",
         "libutils",
+        "libselinux",
     ],
 
     static_libs: [

fastboot/Android.mk

@@ -1,25 +0,0 @@
-# Copyright (C) 2007 Google Inc.
-#
-# 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.
-
-LOCAL_PATH:= $(call my-dir)
-
-#
-# Package fastboot-related executables.
-#
-
-my_dist_files := $(HOST_OUT_EXECUTABLES)/mke2fs
-my_dist_files += $(HOST_OUT_EXECUTABLES)/make_f2fs
-my_dist_files += $(HOST_OUT_EXECUTABLES)/make_f2fs_casefold
-$(call dist-for-goals,dist_files sdk,$(my_dist_files))
-my_dist_files :=

fastboot/fuzzy_fastboot/transport_sniffer.cpp

@@ -90,7 +90,7 @@ std::string TransportSniffer::CreateTrace() {
     // and be printed as a string, or just a raw byte-buffer
     const auto msg = [&ret, no_print](const std::vector<char>& buf) {
         ret += android::base::StringPrintf("(%lu bytes): ", buf.size());
-        std::vector<const char>::iterator iter = buf.end();
+        std::vector<char>::const_iterator iter = buf.end();
         const unsigned max_chars = 50;
         if (buf.size() > max_chars) {
             iter = buf.begin() + max_chars;

fastboot/vendor_boot_img_utils_test.cpp

@@ -163,7 +163,7 @@ struct TestFileHandle {
   protected:
     // |rel_path| is the relative path under test data directory.
     TestFileHandle(const std::filesystem::path& rel_path)
-        : abs_path_(std::move(std::filesystem::path(GetExecutableDirectory()) / rel_path)) {}
+        : abs_path_(std::filesystem::path(GetExecutableDirectory()) / rel_path) {}
     // Given |read_fd|, the readonly fd on the test file, return an fd that's suitable for client
     // to use. Implementation is responsible for managing the lifetime of the returned fd.
     virtual android::base::Result<borrowed_fd> Transform(const std::filesystem::path& abs_path,

fs_mgr/TEST_MAPPING

@@ -33,6 +33,9 @@
     }
   ],
   "kernel-presubmit": [
+    {
+      "name": "adb-remount-sh"
+    },
     {
       "name": "libdm_test"
     },

fs_mgr/fs_mgr.cpp

@@ -28,6 +28,7 @@
 #include <sys/ioctl.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
+#include <sys/statvfs.h>
 #include <sys/swap.h>
 #include <sys/types.h>
 #include <sys/utsname.h>
@@ -37,10 +38,8 @@
 
 #include <array>
 #include <chrono>
-#include <functional>
 #include <map>
 #include <memory>
-#include <numeric>
 #include <string>
 #include <string_view>
 #include <thread>
@@ -65,6 +64,7 @@
 #include <fs_mgr/file_wait.h>
 #include <fs_mgr_overlayfs.h>
 #include <fscrypt/fscrypt.h>
+#include <fstab/fstab.h>
 #include <libdm/dm.h>
 #include <libdm/loop_control.h>
 #include <liblp/metadata_format.h>
@@ -81,7 +81,7 @@
 #define F2FS_FSCK_BIN   "/system/bin/fsck.f2fs"
 #define MKSWAP_BIN      "/system/bin/mkswap"
 #define TUNE2FS_BIN     "/system/bin/tune2fs"
-#define RESIZE2FS_BIN "/system/bin/resize2fs"
+#define RESIZE2FS_BIN   "/system/bin/resize2fs"
 
 #ifdef __ANDROID_RECOVERY__
 #define FSCK_LOG_FILE   "/dev/null"
@@ -141,8 +141,8 @@ enum FsStatFlags {
 static void log_fs_stat(const std::string& blk_device, int fs_stat) {
     std::string msg =
             android::base::StringPrintf("\nfs_stat,%s,0x%x\n", blk_device.c_str(), fs_stat);
-    android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(FSCK_LOG_FILE, O_WRONLY | O_CLOEXEC |
+    android::base::unique_fd fd(TEMP_FAILURE_RETRY(
-                                                        O_APPEND | O_CREAT, 0664)));
+            open(FSCK_LOG_FILE, O_WRONLY | O_CLOEXEC | O_APPEND | O_CREAT, 0664)));
     if (fd == -1 || !android::base::WriteStringToFd(msg, fd)) {
         LWARNING << __FUNCTION__ << "() cannot log " << msg;
     }
@@ -219,10 +219,6 @@ static void check_fs(const std::string& blk_device, const std::string& fs_type,
          */
         if (!(*fs_stat & FS_STAT_FULL_MOUNT_FAILED)) {  // already tried if full mount failed
             errno = 0;
-            if (fs_type == "ext4") {
-                // This option is only valid with ext4
-                tmpmnt_opts += ",nomblk_io_submit";
-            }
             ret = mount(blk_device.c_str(), target.c_str(), fs_type.c_str(), tmpmnt_flags,
                         tmpmnt_opts.c_str());
             PINFO << __FUNCTION__ << "(): mount(" << blk_device << "," << target << "," << fs_type
@@ -600,7 +596,7 @@ static void tune_metadata_csum(const std::string& blk_device, const FstabEntry&
 
     // Must give `-T now` to prevent last_fsck_time from growing too large,
     // otherwise, tune2fs won't enable metadata_csum.
-    const char* tune2fs_args[] = {TUNE2FS_BIN, "-O",        "metadata_csum,64bit,extent",
+    const char* tune2fs_args[] = {TUNE2FS_BIN, "-O",  "metadata_csum,64bit,extent",
                                   "-T",        "now", blk_device.c_str()};
     const char* resize2fs_args[] = {RESIZE2FS_BIN, "-b", blk_device.c_str()};
 
@@ -936,7 +932,8 @@ static bool should_use_metadata_encryption(const FstabEntry& entry) {
 // attempted_idx: On return, will indicate which fstab entry
 //     succeeded. In case of failure, it will be the start_idx.
 // Sets errno to match the 1st mount failure on failure.
-static bool mount_with_alternatives(Fstab& fstab, int start_idx, int* end_idx, int* attempted_idx) {
+static bool mount_with_alternatives(Fstab& fstab, int start_idx, bool interrupted, int* end_idx,
+                                    int* attempted_idx) {
     unsigned long i;
     int mount_errno = 0;
     bool mounted = false;
@@ -955,6 +952,13 @@ static bool mount_with_alternatives(Fstab& fstab, int start_idx, int* end_idx, i
             continue;
         }
 
+        if (interrupted) {
+            LINFO << __FUNCTION__ << "(): skipping fstab mountpoint=" << fstab[i].mount_point
+                  << " rec[" << i << "].fs_type=" << fstab[i].fs_type
+                  << " (previously interrupted during encryption step)";
+            continue;
+        }
+
         // fstab[start_idx].blk_device is already updated to /dev/dm-<N> by
         // AVB related functions. Copy it from start_idx to the current index i.
         if ((i != start_idx) && fstab[i].fs_mgr_flags.logical &&
@@ -1422,19 +1426,59 @@ static bool IsMountPointMounted(const std::string& mount_point) {
     return GetEntryForMountPoint(&fstab, mount_point) != nullptr;
 }
 
+std::string fs_mgr_metadata_encryption_in_progress_file_name(const FstabEntry& entry) {
+    return entry.metadata_key_dir + "/in_progress";
+}
+
+bool WasMetadataEncryptionInterrupted(const FstabEntry& entry) {
+    if (!should_use_metadata_encryption(entry)) return false;
+    return access(fs_mgr_metadata_encryption_in_progress_file_name(entry).c_str(), R_OK) == 0;
+}
+
+static FstabEntry* LocateFormattableEntry(FstabEntry* const begin, FstabEntry* const end) {
+    if (begin == end) {
+        return nullptr;
+    }
+    const bool dev_option_enabled =
+            android::base::GetBoolProperty("ro.product.build.16k_page.enabled", false);
+    FstabEntry* f2fs_entry = nullptr;
+    for (auto iter = begin; iter != end && iter->blk_device == begin->blk_device; iter++) {
+        if (iter->fs_mgr_flags.formattable) {
+            if (getpagesize() != 4096 && is_f2fs(iter->fs_type) && dev_option_enabled) {
+                f2fs_entry = iter;
+                continue;
+            }
+            if (f2fs_entry) {
+                LOG(INFO) << "Skipping F2FS format for block device " << iter->blk_device << " @ "
+                          << iter->mount_point
+                          << " in non-4K mode for dev option enabled devices, "
+                             "as these devices need to toggle between 4K/16K mode, and F2FS does "
+                             "not support page_size != block_size configuration.";
+            }
+            return iter;
+        }
+    }
+    if (f2fs_entry) {
+        LOG(INFO) << "Using F2FS for " << f2fs_entry->blk_device << " @ " << f2fs_entry->mount_point
+                  << " even though we are in non-4K mode. Device might require a data wipe after "
+                     "going back to 4K mode, as F2FS does not support page_size != block_size";
+    }
+    return f2fs_entry;
+}
+
 // When multiple fstab records share the same mount_point, it will try to mount each
 // one in turn, and ignore any duplicates after a first successful mount.
 // Returns -1 on error, and  FS_MGR_MNTALL_* otherwise.
-MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
+int fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
     int encryptable = FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE;
     int error_count = 0;
     CheckpointManager checkpoint_manager;
     AvbUniquePtr avb_handle(nullptr);
     bool wiped = false;
-
     bool userdata_mounted = false;
+
     if (fstab->empty()) {
-        return {FS_MGR_MNTALL_FAIL, userdata_mounted};
+        return FS_MGR_MNTALL_FAIL;
     }
 
     bool scratch_can_be_mounted = true;
@@ -1513,7 +1557,7 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
                 if (!avb_handle) {
                     LERROR << "Failed to open AvbHandle";
                     set_type_property(encryptable);
-                    return {FS_MGR_MNTALL_FAIL, userdata_mounted};
+                    return FS_MGR_MNTALL_FAIL;
                 }
             }
             if (avb_handle->SetUpAvbHashtree(&current_entry, true /* wait_for_verity_dev */) ==
@@ -1532,11 +1576,13 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
             }
         }
 
-        int last_idx_inspected;
+        int last_idx_inspected = -1;
-        int top_idx = i;
+        const int top_idx = i;
         int attempted_idx = -1;
 
-        bool mret = mount_with_alternatives(*fstab, i, &last_idx_inspected, &attempted_idx);
+        bool encryption_interrupted = WasMetadataEncryptionInterrupted(current_entry);
+        bool mret = mount_with_alternatives(*fstab, i, encryption_interrupted, &last_idx_inspected,
+                                            &attempted_idx);
         auto& attempted_entry = (*fstab)[attempted_idx];
         i = last_idx_inspected;
         int mount_errno = errno;
@@ -1547,7 +1593,7 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
 
             if (status == FS_MGR_MNTALL_FAIL) {
                 // Fatal error - no point continuing.
-                return {status, userdata_mounted};
+                return status;
             }
 
             if (status != FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE) {
@@ -1562,11 +1608,12 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
                                    attempted_entry.mount_point, wiped ? "true" : "false",
                                    attempted_entry.fs_type,
                                    attempted_entry.fs_mgr_flags.is_zoned ? "true" : "false",
+                                   std::to_string(attempted_entry.length),
                                    android::base::Join(attempted_entry.user_devices, ' ')},
                                   nullptr)) {
                         LERROR << "Encryption failed";
                         set_type_property(encryptable);
-                        return {FS_MGR_MNTALL_FAIL, userdata_mounted};
+                        return FS_MGR_MNTALL_FAIL;
                     }
                 }
             }
@@ -1580,17 +1627,23 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
             // Success!  Go get the next one.
             continue;
         }
-
+        auto formattable_entry =
+                LocateFormattableEntry(fstab->data() + top_idx, fstab->data() + fstab->size());
         // Mounting failed, understand why and retry.
         wiped = partition_wiped(current_entry.blk_device.c_str());
         if (mount_errno != EBUSY && mount_errno != EACCES &&
-            current_entry.fs_mgr_flags.formattable && wiped) {
+            current_entry.fs_mgr_flags.formattable && (wiped || encryption_interrupted)) {
             // current_entry and attempted_entry point at the same partition, but sometimes
             // at two different lines in the fstab.  Use current_entry for formatting
             // as that is the preferred one.
-            LERROR << __FUNCTION__ << "(): " << realpath(current_entry.blk_device)
+            if (wiped)
-                   << " is wiped and " << current_entry.mount_point << " " << current_entry.fs_type
+                LERROR << __FUNCTION__ << "(): " << realpath(current_entry.blk_device)
-                   << " is formattable. Format it.";
+                       << " is wiped and " << current_entry.mount_point << " "
+                       << current_entry.fs_type << " is formattable. Format it.";
+            if (encryption_interrupted)
+                LERROR << __FUNCTION__ << "(): " << realpath(current_entry.blk_device)
+                       << " was interrupted during encryption and " << current_entry.mount_point
+                       << " " << current_entry.fs_type << " is formattable. Format it.";
 
             checkpoint_manager.Revert(&current_entry);
 
@@ -1603,11 +1656,12 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
                 encryptable = FS_MGR_MNTALL_DEV_IS_METADATA_ENCRYPTED;
                 set_type_property(encryptable);
 
-                if (!call_vdc({"cryptfs", "encryptFstab", current_entry.blk_device,
+                if (!call_vdc({"cryptfs", "encryptFstab", formattable_entry->blk_device,
-                               current_entry.mount_point, "true" /* shouldFormat */,
+                               formattable_entry->mount_point, "true" /* shouldFormat */,
-                               current_entry.fs_type,
+                               formattable_entry->fs_type,
-                               current_entry.fs_mgr_flags.is_zoned ? "true" : "false",
+                               formattable_entry->fs_mgr_flags.is_zoned ? "true" : "false",
-                               android::base::Join(current_entry.user_devices, ' ')},
+                               std::to_string(formattable_entry->length),
+                               android::base::Join(formattable_entry->user_devices, ' ')},
                               nullptr)) {
                     LERROR << "Encryption failed";
                 } else {
@@ -1616,7 +1670,7 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
                 }
             }
 
-            if (fs_mgr_do_format(current_entry) == 0) {
+            if (fs_mgr_do_format(*formattable_entry) == 0) {
                 // Let's replay the mount actions.
                 i = top_idx - 1;
                 continue;
@@ -1629,7 +1683,7 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
         }
 
         // mount(2) returned an error, handle the encryptable/formattable case.
-        if (mount_errno != EBUSY && mount_errno != EACCES &&
+        if (mount_errno != EBUSY && mount_errno != EACCES && !encryption_interrupted &&
             should_use_metadata_encryption(attempted_entry)) {
             if (!call_vdc({"cryptfs", "mountFstab", attempted_entry.blk_device,
                            attempted_entry.mount_point,
@@ -1647,13 +1701,13 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
             // Use StringPrintf to output "(null)" instead.
             if (attempted_entry.fs_mgr_flags.no_fail) {
                 PERROR << android::base::StringPrintf(
-                        "Ignoring failure to mount an un-encryptable or wiped "
+                        "Ignoring failure to mount an un-encryptable, interrupted, or wiped "
                         "partition on %s at %s options: %s",
                         attempted_entry.blk_device.c_str(), attempted_entry.mount_point.c_str(),
                         attempted_entry.fs_options.c_str());
             } else {
                 PERROR << android::base::StringPrintf(
-                        "Failed to mount an un-encryptable or wiped partition "
+                        "Failed to mount an un-encryptable, interrupted, or wiped partition "
                         "on %s at %s options: %s",
                         attempted_entry.blk_device.c_str(), attempted_entry.mount_point.c_str(),
                         attempted_entry.fs_options.c_str());
@@ -1679,9 +1733,9 @@ MountAllResult fs_mgr_mount_all(Fstab* fstab, int mount_mode) {
     set_type_property(encryptable);
 
     if (error_count) {
-        return {FS_MGR_MNTALL_FAIL, userdata_mounted};
+        return FS_MGR_MNTALL_FAIL;
     } else {
-        return {encryptable, userdata_mounted};
+        return encryptable;
     }
 }
 
@@ -1718,190 +1772,6 @@ int fs_mgr_umount_all(android::fs_mgr::Fstab* fstab) {
     return ret;
 }
 
-static std::chrono::milliseconds GetMillisProperty(const std::string& name,
-                                                   std::chrono::milliseconds default_value) {
-    auto value = GetUintProperty(name, static_cast<uint64_t>(default_value.count()));
-    return std::chrono::milliseconds(std::move(value));
-}
-
-static bool fs_mgr_unmount_all_data_mounts(const std::string& data_block_device) {
-    LINFO << __FUNCTION__ << "(): about to umount everything on top of " << data_block_device;
-    Timer t;
-    auto timeout = GetMillisProperty("init.userspace_reboot.userdata_remount.timeoutmillis", 5s);
-    while (true) {
-        bool umount_done = true;
-        Fstab proc_mounts;
-        if (!ReadFstabFromFile("/proc/mounts", &proc_mounts)) {
-            LERROR << __FUNCTION__ << "(): Can't read /proc/mounts";
-            return false;
-        }
-        // Now proceed with other bind mounts on top of /data.
-        for (const auto& entry : proc_mounts) {
-            std::string block_device;
-            if (StartsWith(entry.blk_device, "/dev/block") &&
-                !Realpath(entry.blk_device, &block_device)) {
-                PWARNING << __FUNCTION__ << "(): failed to realpath " << entry.blk_device;
-                block_device = entry.blk_device;
-            }
-            if (data_block_device == block_device) {
-                if (umount2(entry.mount_point.c_str(), 0) != 0) {
-                    PERROR << __FUNCTION__ << "(): Failed to umount " << entry.mount_point;
-                    umount_done = false;
-                }
-            }
-        }
-        if (umount_done) {
-            LINFO << __FUNCTION__ << "(): Unmounting /data took " << t;
-            return true;
-        }
-        if (t.duration() > timeout) {
-            LERROR << __FUNCTION__ << "(): Timed out unmounting all mounts on "
-                   << data_block_device;
-            Fstab remaining_mounts;
-            if (!ReadFstabFromFile("/proc/mounts", &remaining_mounts)) {
-                LERROR << __FUNCTION__ << "(): Can't read /proc/mounts";
-            } else {
-                LERROR << __FUNCTION__ << "(): Following mounts remaining";
-                for (const auto& e : remaining_mounts) {
-                    LERROR << __FUNCTION__ << "(): mount point: " << e.mount_point
-                           << " block device: " << e.blk_device;
-                }
-            }
-            return false;
-        }
-        std::this_thread::sleep_for(50ms);
-    }
-}
-
-static bool UnwindDmDeviceStack(const std::string& block_device,
-                                std::vector<std::string>* dm_stack) {
-    if (!StartsWith(block_device, "/dev/block/")) {
-        LWARNING << block_device << " is not a block device";
-        return false;
-    }
-    std::string current = block_device;
-    DeviceMapper& dm = DeviceMapper::Instance();
-    while (true) {
-        dm_stack->push_back(current);
-        if (!dm.IsDmBlockDevice(current)) {
-            break;
-        }
-        auto parent = dm.GetParentBlockDeviceByPath(current);
-        if (!parent) {
-            return false;
-        }
-        current = *parent;
-    }
-    return true;
-}
-
-FstabEntry* fs_mgr_get_mounted_entry_for_userdata(Fstab* fstab,
-                                                  const std::string& data_block_device) {
-    std::vector<std::string> dm_stack;
-    if (!UnwindDmDeviceStack(data_block_device, &dm_stack)) {
-        LERROR << "Failed to unwind dm-device stack for " << data_block_device;
-        return nullptr;
-    }
-    for (auto& entry : *fstab) {
-        if (entry.mount_point != "/data") {
-            continue;
-        }
-        std::string block_device;
-        if (entry.fs_mgr_flags.logical) {
-            if (!fs_mgr_update_logical_partition(&entry)) {
-                LERROR << "Failed to update logic partition " << entry.blk_device;
-                continue;
-            }
-            block_device = entry.blk_device;
-        } else if (!Realpath(entry.blk_device, &block_device)) {
-            PWARNING << "Failed to realpath " << entry.blk_device;
-            block_device = entry.blk_device;
-        }
-        if (std::find(dm_stack.begin(), dm_stack.end(), block_device) != dm_stack.end()) {
-            return &entry;
-        }
-    }
-    LERROR << "Didn't find entry that was used to mount /data onto " << data_block_device;
-    return nullptr;
-}
-
-// TODO(b/143970043): return different error codes based on which step failed.
-int fs_mgr_remount_userdata_into_checkpointing(Fstab* fstab) {
-    Fstab proc_mounts;
-    if (!ReadFstabFromFile("/proc/mounts", &proc_mounts)) {
-        LERROR << "Can't read /proc/mounts";
-        return -1;
-    }
-    auto mounted_entry = GetEntryForMountPoint(&proc_mounts, "/data");
-    if (mounted_entry == nullptr) {
-        LERROR << "/data is not mounted";
-        return -1;
-    }
-    std::string block_device;
-    if (!Realpath(mounted_entry->blk_device, &block_device)) {
-        PERROR << "Failed to realpath " << mounted_entry->blk_device;
-        return -1;
-    }
-    auto fstab_entry = fs_mgr_get_mounted_entry_for_userdata(fstab, block_device);
-    if (fstab_entry == nullptr) {
-        LERROR << "Can't find /data in fstab";
-        return -1;
-    }
-    bool force_umount = GetBoolProperty("sys.init.userdata_remount.force_umount", false);
-    if (force_umount) {
-        LINFO << "Will force an umount of userdata even if it's not required";
-    }
-    if (!force_umount && !SupportsCheckpoint(fstab_entry)) {
-        LINFO << "Userdata doesn't support checkpointing. Nothing to do";
-        return 0;
-    }
-    CheckpointManager checkpoint_manager;
-    if (!force_umount && !checkpoint_manager.NeedsCheckpoint()) {
-        LINFO << "Checkpointing not needed. Don't remount";
-        return 0;
-    }
-    if (!force_umount && fstab_entry->fs_mgr_flags.checkpoint_fs) {
-        // Userdata is f2fs, simply remount it.
-        if (!checkpoint_manager.Update(fstab_entry)) {
-            LERROR << "Failed to remount userdata in checkpointing mode";
-            return -1;
-        }
-        if (mount(block_device.c_str(), fstab_entry->mount_point.c_str(), "none",
-                  MS_REMOUNT | fstab_entry->flags, fstab_entry->fs_options.c_str()) != 0) {
-            PERROR << "Failed to remount userdata in checkpointing mode";
-            return -1;
-        }
-    } else {
-        LINFO << "Unmounting /data before remounting into checkpointing mode";
-        if (!fs_mgr_unmount_all_data_mounts(block_device)) {
-            LERROR << "Failed to umount /data";
-            return -1;
-        }
-        DeviceMapper& dm = DeviceMapper::Instance();
-        while (dm.IsDmBlockDevice(block_device)) {
-            auto next_device = dm.GetParentBlockDeviceByPath(block_device);
-            auto name = dm.GetDmDeviceNameByPath(block_device);
-            if (!name) {
-                LERROR << "Failed to get dm-name for " << block_device;
-                return -1;
-            }
-            LINFO << "Deleting " << block_device << " named " << *name;
-            if (!dm.DeleteDevice(*name, 3s)) {
-                return -1;
-            }
-            if (!next_device) {
-                LERROR << "Failed to find parent device for " << block_device;
-            }
-            block_device = *next_device;
-        }
-        LINFO << "Remounting /data";
-        // TODO(b/143970043): remove this hack after fs_mgr_mount_all is refactored.
-        auto result = fs_mgr_mount_all(fstab, MOUNT_MODE_ONLY_USERDATA);
-        return result.code == FS_MGR_MNTALL_FAIL ? -1 : 0;
-    }
-    return 0;
-}
-
 // wrapper to __mount() and expects a fully prepared fstab_rec,
 // unlike fs_mgr_do_mount which does more things with avb / verity etc.
 int fs_mgr_do_mount_one(const FstabEntry& entry, const std::string& alt_mount_point) {
@@ -1916,12 +1786,12 @@ int fs_mgr_do_mount_one(const FstabEntry& entry, const std::string& alt_mount_po
     int ret = prepare_fs_for_mount(entry.blk_device, entry, mount_point);
     // Wiped case doesn't require to try __mount below.
     if (ret & FS_STAT_INVALID_MAGIC) {
-      return FS_MGR_DOMNT_FAILED;
+        return FS_MGR_DOMNT_FAILED;
     }
 
     ret = __mount(entry.blk_device, mount_point, entry);
     if (ret) {
-      ret = (errno == EBUSY) ? FS_MGR_DOMNT_BUSY : FS_MGR_DOMNT_FAILED;
+        ret = (errno == EBUSY) ? FS_MGR_DOMNT_BUSY : FS_MGR_DOMNT_FAILED;
     }
 
     return ret;
@@ -2073,11 +1943,45 @@ static bool InstallZramDevice(const std::string& device) {
     return true;
 }
 
+/*
+ * Zram backing device can be created as long as /data has at least `size`
+ * free space, though we may want to leave some extra space for the remaining
+ * boot process and other system activities.
+ */
+static bool ZramBackingDeviceSizeAvailable(off64_t size) {
+    constexpr const char* data_path = "/data";
+    uint64_t min_free_mb =
+            android::base::GetUintProperty<uint64_t>("ro.zram_backing_device_min_free_mb", 0);
+
+    // No min_free property. Skip the available size check.
+    if (min_free_mb == 0) return true;
+
+    struct statvfs vst;
+    if (statvfs(data_path, &vst) < 0) {
+        PERROR << "Cannot check available space: " << data_path;
+        return false;
+    }
+
+    uint64_t size_free = static_cast<uint64_t>(vst.f_bfree) * vst.f_frsize;
+    uint64_t size_required = size + (min_free_mb * 1024 * 1024);
+    if (size_required > size_free) {
+        PERROR << "Free space is not enough for zram backing device: " << size_required << " > "
+               << size_free;
+        return false;
+    }
+    return true;
+}
+
 static bool PrepareZramBackingDevice(off64_t size) {
 
     constexpr const char* file_path = "/data/per_boot/zram_swap";
     if (size == 0) return true;
 
+    // Check available space
+    if (!ZramBackingDeviceSizeAvailable(size)) {
+        PERROR << "No space for target path: " << file_path;
+        return false;
+    }
     // Prepare target path
     unique_fd target_fd(TEMP_FAILURE_RETRY(open(file_path, O_RDWR | O_CREAT | O_CLOEXEC, 0600)));
     if (target_fd.get() == -1) {
@@ -2086,6 +1990,7 @@ static bool PrepareZramBackingDevice(off64_t size) {
     }
     if (fallocate(target_fd.get(), 0, 0, size) < 0) {
         PERROR << "Cannot truncate target path: " << file_path;
+        unlink(file_path);
         return false;
     }
 

fs_mgr/fs_mgr_overlayfs_mount.cpp

@@ -74,7 +74,7 @@ bool fs_mgr_is_dsu_running() {
     return android::gsi::IsGsiRunning();
 }
 
-std::vector<const std::string> OverlayMountPoints() {
+std::vector<std::string> OverlayMountPoints() {
     // Never fallback to legacy cache mount point if within a DSU system,
     // because running a DSU system implies the device supports dynamic
     // partitions, which means legacy cache mustn't be used.
@@ -412,6 +412,8 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
     bool retval = true;
     bool move_dir_shared = true;
     bool parent_shared = true;
+    bool parent_have_parent = false;
+    bool parent_made_private = false;
     bool root_shared = true;
     bool root_made_private = false;
 
@@ -443,6 +445,10 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
         if (entry.mount_point == "/") {
             root_shared = entry.shared_flag;
         }
+        // Ignore "/" as we don't overlay "/" directly.
+        if (entry.mount_point != "/") {
+            parent_have_parent |= android::base::StartsWith(mount_point, entry.mount_point + "/");
+        }
     }
 
     // Precondition is that kMoveMountTempDir is MS_PRIVATE, otherwise don't try to move any
@@ -453,11 +459,13 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
 
     // Need to make the original mountpoint MS_PRIVATE, so that the overlayfs can be MS_MOVE.
     // This could happen if its parent mount is remounted later.
-    if (!fs_mgr_overlayfs_set_shared_mount(mount_point, false)) {
+    if (parent_have_parent) {
-        // If failed to set "/system" mount type, it might be due to "/system" not being a valid
+        parent_made_private |= fs_mgr_overlayfs_set_shared_mount(mount_point, false);
-        // mountpoint after switch root. Retry with "/" in this case.
+        if (!parent_made_private && errno == EINVAL && mount_point == "/system") {
-        if (errno == EINVAL && mount_point == "/system") {
+            // If failed to set "/system" mount type, it might be due to "/system" not being a valid
-            root_made_private = fs_mgr_overlayfs_set_shared_mount("/", false);
+            // mountpoint after switch root. Retry with "/" in this case.
+            parent_made_private |= fs_mgr_overlayfs_set_shared_mount("/", false);
+            root_made_private |= parent_made_private;
         }
     }
 
@@ -496,6 +504,15 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
                 continue;
             }
         }
+        if (!parent_made_private) {
+            parent_made_private |= fs_mgr_overlayfs_set_shared_mount(mount_point, false);
+            if (!parent_made_private && errno == EINVAL && mount_point == "/system") {
+                // If failed to set "/system" mount type, it might be due to "/system" not being a
+                // valid mountpoint after switch root. Retry with "/" in this case.
+                parent_made_private |= fs_mgr_overlayfs_set_shared_mount("/", false);
+                root_made_private |= parent_made_private;
+            }
+        }
 
         if (new_entry.shared_flag) {
             new_entry.shared_flag = fs_mgr_overlayfs_set_shared_mount(new_entry.mount_point, false);
@@ -524,7 +541,7 @@ static bool fs_mgr_overlayfs_mount_one(const FstabEntry& fstab_entry) {
         rmdir(entry.dir.c_str());
     }
     // If the original (overridden) mount was MS_SHARED, then set the overlayfs mount to MS_SHARED.
-    if (parent_shared) {
+    if (parent_shared && parent_made_private) {
         fs_mgr_overlayfs_set_shared_mount(mount_point, true);
     }
     if (root_shared && root_made_private) {

fs_mgr/fs_mgr_overlayfs_mount.h

@@ -54,7 +54,7 @@ const std::string fs_mgr_mount_point(const std::string& mount_point);
 bool OverlayfsSetupAllowed(bool verbose = false);
 bool MountScratch(const std::string& device_path, bool readonly = false);
 bool fs_mgr_overlayfs_umount_scratch();
-std::vector<const std::string> OverlayMountPoints();
+std::vector<std::string> OverlayMountPoints();
 bool fs_mgr_overlayfs_already_mounted(const std::string& mount_point, bool overlay_only = true);
 bool fs_mgr_wants_overlayfs(android::fs_mgr::FstabEntry* entry);
 android::fs_mgr::Fstab fs_mgr_overlayfs_candidate_list(const android::fs_mgr::Fstab& fstab);

fs_mgr/fs_mgr_priv.h

@@ -80,10 +80,8 @@
 
 using namespace std::chrono_literals;
 
-bool fs_mgr_set_blk_ro(const std::string& blockdev, bool readonly = true);
 bool fs_mgr_is_device_unlocked();
 
-bool fs_mgr_is_ext4(const std::string& blk_device);
 bool fs_mgr_is_f2fs(const std::string& blk_device);
 
 bool fs_mgr_filesystem_available(const std::string& filesystem);

fs_mgr/fs_mgr_remount.cpp

@@ -171,11 +171,12 @@ bool VerifyCheckpointing() {
         }
         if (show_help) {
             show_help = false;
-            std::cerr << "WARNING: Userdata checkpoint is in progress. To force end checkpointing, "
+            std::cerr << "WARNING: Userdata checkpoint is in progress. "
-                         "call 'vdc checkpoint commitChanges'. This can lead to data corruption if "
+                         "To forcibly end checkpointing, "
-                         "rolled back."
+                         "call 'vdc checkpoint commitChanges'. "
+                         "This can lead to data corruption if rolled back."
                       << std::endl;
-            LOG(INFO) << "Waiting for checkpoint to complete and then continue remount.";
+            LOG(INFO) << "Waiting for checkpoint to complete before remounting...";
         }
         std::this_thread::sleep_for(4s);
     }

fs_mgr/fs_mgr_vendor_overlay.cpp

@@ -36,7 +36,7 @@ namespace {
 
 // The order of the list means the priority to show the files in the directory.
 // The last one has the highest priority.
-const std::vector<const std::string> kVendorOverlaySourceDirs = {
+const std::vector<std::string> kVendorOverlaySourceDirs = {
         "/system/vendor_overlay/",
         "/product/vendor_overlay/",
 };

fs_mgr/include/fs_mgr.h

@@ -58,13 +58,8 @@ enum mount_mode {
 #define FS_MGR_MNTALL_DEV_NEEDS_RECOVERY 4
 #define FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE 0
 #define FS_MGR_MNTALL_FAIL (-1)
-
+// fs_mgr_mount_all() updates fstab entries that reference device-mapper.
-struct MountAllResult {
+int fs_mgr_mount_all(android::fs_mgr::Fstab* fstab, int mount_mode);
-    // One of the FS_MGR_MNTALL_* returned code defined above.
-    int code;
-    // Whether userdata was mounted as a result of |fs_mgr_mount_all| call.
-    bool userdata_mounted;
-};
 
 struct HashtreeInfo {
     // The hash algorithm used to build the merkle tree.
@@ -75,13 +70,6 @@ struct HashtreeInfo {
     bool check_at_most_once;
 };
 
-// fs_mgr_mount_all() updates fstab entries that reference device-mapper.
-// Returns a |MountAllResult|. The first element is one of the FS_MNG_MNTALL_* return codes
-// defined above, and the second element tells whether this call to fs_mgr_mount_all was responsible
-// for mounting userdata. Later is required for init to correctly enqueue fs-related events as part
-// of userdata remount during userspace reboot.
-MountAllResult fs_mgr_mount_all(android::fs_mgr::Fstab* fstab, int mount_mode);
-
 #define FS_MGR_DOMNT_FAILED (-1)
 #define FS_MGR_DOMNT_BUSY (-2)
 #define FS_MGR_DOMNT_SUCCESS 0
@@ -116,6 +104,12 @@ int fs_mgr_setup_verity(android::fs_mgr::FstabEntry* fstab, bool wait_for_verity
 // returned. Otherwise, it will use the current slot.
 std::string fs_mgr_get_super_partition_name(int slot = -1);
 
+// Set readonly for the block device
+bool fs_mgr_set_blk_ro(const std::string& blockdev, bool readonly = true);
+
+// Check if the block device has ext4 filesystem
+bool fs_mgr_is_ext4(const std::string& blk_device);
+
 enum FsMgrUmountStatus : int {
     SUCCESS = 0,
     ERROR_UNKNOWN = 1 << 0,
@@ -127,11 +121,6 @@ enum FsMgrUmountStatus : int {
 // it destroys verity devices from device mapper after the device is unmounted.
 int fs_mgr_umount_all(android::fs_mgr::Fstab* fstab);
 
-// Finds a entry in |fstab| that was used to mount a /data on |data_block_device|.
-android::fs_mgr::FstabEntry* fs_mgr_get_mounted_entry_for_userdata(
-        android::fs_mgr::Fstab* fstab, const std::string& data_block_device);
-int fs_mgr_remount_userdata_into_checkpointing(android::fs_mgr::Fstab* fstab);
-
 // Finds the dm_bow device on which this block device is stacked, or returns
 // empty string
 std::string fs_mgr_find_bow_device(const std::string& block_device);
@@ -144,3 +133,7 @@ bool fs_mgr_create_canonical_mount_point(const std::string& mount_point);
 // Unlike fs_mgr_overlayfs, mount overlayfs without upperdir and workdir, so the
 // filesystem cannot be remount read-write.
 bool fs_mgr_mount_overlayfs_fstab_entry(const android::fs_mgr::FstabEntry& entry);
+
+// File name used to track if encryption was interrupted, leading to a known bad fs state
+std::string fs_mgr_metadata_encryption_in_progress_file_name(
+        const android::fs_mgr::FstabEntry& entry);

fs_mgr/include/fs_mgr/roots.h

@@ -29,6 +29,8 @@ namespace fs_mgr {
 // first match or nullptr.
 FstabEntry* GetEntryForPath(Fstab* fstab, const std::string& path);
 
+std::vector<FstabEntry*> GetEntriesForPath(Fstab* fstab, const std::string& path);
+
 // Make sure that the volume 'path' is on is mounted.
 // * If 'mount_point' is nullptr, use mount point in fstab. Caller can call
 //   fs_mgr_ensure_path_unmounted() with the same 'path' argument to unmount.

fs_mgr/libfiemap/fiemap_writer.cpp

@@ -60,6 +60,7 @@ static_assert(sizeof(off_t) == sizeof(uint64_t));
 static inline void cleanup(const std::string& file_path, bool created) {
     if (created) {
         unlink(file_path.c_str());
+        sync();
     }
 }
 

fs_mgr/libfs_avb/avb_ops.cpp

@@ -34,6 +34,7 @@
 
 #include <string>
 
+#include <android-base/logging.h>
 #include <android-base/macros.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>

fs_mgr/libfs_avb/avb_util.cpp

@@ -21,6 +21,7 @@
 #include <array>
 #include <sstream>
 
+#include <android-base/logging.h>
 #include <android-base/file.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>

fs_mgr/libfs_avb/fs_avb.cpp

@@ -28,6 +28,7 @@
 #include <vector>
 
 #include <android-base/file.h>
+#include <android-base/logging.h>
 #include <android-base/parseint.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>

fs_mgr/libfs_avb/fs_avb_util.cpp

@@ -20,6 +20,7 @@
 #include <string>
 #include <vector>
 
+#include <android-base/logging.h>
 #include <android-base/strings.h>
 #include <fstab/fstab.h>
 #include <libavb/libavb.h>

fs_mgr/libfs_avb/tests/avb_util_test.cpp

@@ -16,10 +16,11 @@
 
 #include <endian.h>
 
+#include <random>
+
+#include <android-base/strings.h>
 #include <android-base/unique_fd.h>
 #include <base/files/file_util.h>
-#include <base/rand_util.h>
-#include <base/strings/string_util.h>
 #include <libavb/libavb.h>
 
 #include "avb_util.h"
@@ -70,7 +71,7 @@ void AvbUtilTest::SetVBMetaFlags(const base::FilePath& image_path, uint32_t flag
 
     std::string image_file_name = image_path.RemoveExtension().BaseName().value();
     bool is_vbmeta_partition =
-        base::StartsWith(image_file_name, "vbmeta", base::CompareCase::INSENSITIVE_ASCII);
+        android::base::StartsWithIgnoreCase(image_file_name, "vbmeta");
 
     android::base::unique_fd fd(open(image_path.value().c_str(), O_RDWR | O_CLOEXEC));
     EXPECT_TRUE(fd > 0);
@@ -603,7 +604,7 @@ bool AvbUtilTest::CompareVBMeta(const base::FilePath& avb_image_path,
     std::string image_file_name = avb_image_path.RemoveExtension().BaseName().value();
 
     base::FilePath extracted_vbmeta_path;
-    if (base::StartsWith(image_file_name, "vbmeta", base::CompareCase::INSENSITIVE_ASCII)) {
+    if (android::base::StartsWithIgnoreCase(image_file_name, "vbmeta")) {
         extracted_vbmeta_path = avb_image_path;  // no need to extract if it's a vbmeta image.
     } else {
         extracted_vbmeta_path = ExtractVBMetaImage(avb_image_path, image_file_name + "-vbmeta.img");
@@ -727,7 +728,10 @@ void AvbUtilTest::ModifyFile(const base::FilePath& file_path, size_t offset, ssi
 
     // Introduces a new modification.
     if (length > 0) {
-        int modify_location = base::RandInt(offset, offset + length - 1);
+        // mersenne_twister_engine seeded with the default seed source.
+        static std::mt19937 gen(std::random_device{}());
+        std::uniform_int_distribution<> rand_distribution(offset, offset + length - 1);
+        int modify_location = rand_distribution(gen);
         file_content[modify_location] ^= 0x80;
         last_file_path = file_path.value();
         last_modified_location = modify_location;

fs_mgr/libfs_avb/tests/basic_test.cpp

@@ -20,7 +20,6 @@
 
 #include <android-base/file.h>
 #include <base/files/file_util.h>
-#include <base/strings/string_util.h>
 
 namespace fs_avb_host_test {
 

fs_mgr/libfs_avb/tests/fs_avb_test.cpp

@@ -18,8 +18,8 @@
 #include <stdlib.h>
 
 #include <android-base/file.h>
+#include <android-base/strings.h>
 #include <base/files/file_util.h>
-#include <base/strings/string_util.h>
 #include <fs_avb/fs_avb.h>
 #include <libavb/libavb.h>
 
@@ -49,7 +49,7 @@ void PublicFsAvbTest::ModifyVBMetaHeaderFlags(const base::FilePath& vbmeta_image
 
     // Only support modifying the flags in vbmeta*.img.
     std::string image_file_name = vbmeta_image_path.RemoveExtension().BaseName().value();
-    ASSERT_TRUE(base::StartsWith(image_file_name, "vbmeta", base::CompareCase::INSENSITIVE_ASCII));
+    ASSERT_TRUE(android::base::StartsWithIgnoreCase(image_file_name, "vbmeta"));
 
     android::base::unique_fd fd(open(vbmeta_image_path.value().c_str(), O_RDWR | O_CLOEXEC));
     EXPECT_TRUE(fd > 0);

fs_mgr/libfs_avb/tests/fs_avb_test_util.cpp

@@ -19,8 +19,9 @@
 #include <stdlib.h>
 
 #include <android-base/file.h>
+#include <android-base/strings.h>
+#include <android-base/stringprintf.h>
 #include <base/files/file_util.h>
-#include <base/strings/string_util.h>
 
 namespace fs_avb_host_test {
 
@@ -64,9 +65,7 @@ std::string BaseFsAvbTest::CalcVBMetaDigest(const std::string& file_name,
     std::string vbmeta_digest_data;
     EXPECT_TRUE(base::ReadFileToString(vbmeta_digest_path, &vbmeta_digest_data));
     // Returns the trimmed digest.
-    std::string trimmed_digest_data;
+    return android::base::Trim(vbmeta_digest_data);
-    base::TrimString(vbmeta_digest_data, " \t\n", &trimmed_digest_data);
-    return trimmed_digest_data;
 }
 
 base::FilePath BaseFsAvbTest::GenerateVBMetaImage(
@@ -91,7 +90,7 @@ base::FilePath BaseFsAvbTest::GenerateVBMetaImage(
     // --chain_partitions
     std::string chain_partition_options;
     for (const auto& partition : chain_partitions) {
-        chain_partition_options += base::StringPrintf(
+        chain_partition_options += android::base::StringPrintf(
                 " --chain_partition %s:%u:%s", partition.partition_name.c_str(),
                 partition.rollback_index_location, partition.key_blob_path.value().c_str());
     }

fs_mgr/libfs_avb/tests/fs_avb_test_util.h

@@ -26,9 +26,9 @@
 #include <string>
 #include <vector>
 
+#include <android-base/stringprintf.h>
 #include <android-base/unique_fd.h>
 #include <base/files/file_path.h>
-#include <base/strings/stringprintf.h>
 #include <fs_avb/types.h>
 #include <gtest/gtest.h>
 
@@ -37,7 +37,7 @@
 // the command exits normally with exit status |expected_exit_status|.
 #define EXPECT_COMMAND(expected_exit_status, command_format, ...)                   \
     do {                                                                            \
-        int rc = system(base::StringPrintf(command_format, ##__VA_ARGS__).c_str()); \
+        int rc = system(android::base::StringPrintf(command_format, ##__VA_ARGS__).c_str()); \
         EXPECT_TRUE(WIFEXITED(rc));                                                 \
         EXPECT_EQ(WEXITSTATUS(rc), expected_exit_status);                           \
     } while (0);

fs_mgr/libfs_avb/util.cpp

@@ -22,6 +22,7 @@
 
 #include <thread>
 
+#include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android-base/unique_fd.h>
 #include <linux/fs.h>

fs_mgr/libfs_avb/util.h

@@ -20,12 +20,6 @@
 #include <string>
 #include <vector>
 
-#ifdef HOST_TEST
-#include <base/logging.h>
-#else
-#include <android-base/logging.h>
-#endif
-
 #include <android-base/result.h>
 
 using android::base::ErrnoError;

fs_mgr/libfstab/fstab.cpp

@@ -39,6 +39,10 @@
 #include "fstab_priv.h"
 #include "logging_macros.h"
 
+#if !defined(MS_LAZYTIME)
+#define MS_LAZYTIME (1 << 25)
+#endif
+
 using android::base::EndsWith;
 using android::base::ParseByteCount;
 using android::base::ParseInt;
@@ -74,6 +78,7 @@ FlagList kMountFlagsList[] = {
         {"private", MS_PRIVATE},
         {"slave", MS_SLAVE},
         {"shared", MS_SHARED},
+        {"lazytime", MS_LAZYTIME},
         {"defaults", 0},
 };
 
@@ -521,6 +526,24 @@ std::vector<FstabPtrEntryType*> GetEntriesByPred(FstabPtr fstab, const Pred& pre
 
 }  // namespace
 
+// Return the path to the recovery fstab file.  There may be multiple fstab files;
+// the one that is returned will be the first that exists of recovery.fstab.<fstab_suffix>,
+// recovery.fstab.<hardware>, and recovery.fstab.<hardware.platform>.
+std::string GetRecoveryFstabPath() {
+    for (const char* prop : {"fstab_suffix", "hardware", "hardware.platform"}) {
+        std::string suffix;
+
+        if (!fs_mgr_get_boot_config(prop, &suffix)) continue;
+
+        std::string fstab_path = "/etc/recovery.fstab." + suffix;
+        if (access(fstab_path.c_str(), F_OK) == 0) {
+            return fstab_path;
+        }
+    }
+
+    return "/etc/recovery.fstab";
+}
+
 // Return the path to the fstab file.  There may be multiple fstab files; the
 // one that is returned will be the first that exists of fstab.<fstab_suffix>,
 // fstab.<hardware>, and fstab.<hardware.platform>.  The fstab is searched for
@@ -530,7 +553,7 @@ std::vector<FstabPtrEntryType*> GetEntriesByPred(FstabPtr fstab, const Pred& pre
 // the system/etc directory is supported too and is the preferred location.
 std::string GetFstabPath() {
     if (InRecovery()) {
-        return "/etc/recovery.fstab";
+        return GetRecoveryFstabPath();
     }
     for (const char* prop : {"fstab_suffix", "hardware", "hardware.platform"}) {
         std::string suffix;

fs_mgr/libfstab/fstab_priv.h

@@ -39,9 +39,6 @@ std::string GetFstabPath();
 void ImportBootconfigFromString(const std::string& bootconfig,
                                 const std::function<void(std::string, std::string)>& fn);
 
-bool GetBootconfigFromString(const std::string& bootconfig, const std::string& key,
-                             std::string* out);
-
 void ImportKernelCmdlineFromString(const std::string& cmdline,
                                    const std::function<void(std::string, std::string)>& fn);
 

fs_mgr/libfstab/include/fstab/fstab.h

@@ -154,5 +154,8 @@ bool GetKernelCmdline(const std::string& key, std::string* out);
 // Return the "other" slot for the given slot suffix.
 std::string OtherSlotSuffix(const std::string& suffix);
 
+bool GetBootconfigFromString(const std::string& bootconfig, const std::string& key,
+                             std::string* out);
+
 }  // namespace fs_mgr
 }  // namespace android

fs_mgr/libsnapshot/Android.bp

@@ -91,6 +91,7 @@ filegroup {
         "partition_cow_creator.cpp",
         "return.cpp",
         "utility.cpp",
+        "scratch_super.cpp",
     ],
 }
 
@@ -110,6 +111,9 @@ cc_library_static {
     static_libs: [
         "libfs_mgr_binder",
     ],
+    whole_static_libs: [
+        "libselinux",
+    ],
 }
 
 cc_library {
@@ -128,6 +132,9 @@ cc_library {
     static_libs: [
         "libsnapshot_cow",
     ],
+    whole_static_libs: [
+        "libselinux",
+    ],
 }
 
 cc_library_static {
@@ -142,6 +149,7 @@ cc_library_static {
     ],
     static_libs: [
         "libfs_mgr",
+        "libselinux",
     ],
 }
 
@@ -159,6 +167,9 @@ cc_library_static {
     static_libs: [
         "libfs_mgr",
     ],
+    whole_static_libs: [
+        "libselinux",
+    ],
 }
 
 cc_defaults {
@@ -241,6 +252,7 @@ cc_library_static {
         "libfs_mgr",
         "libgmock",
         "libgtest",
+        "libselinux",
     ],
 }
 
@@ -283,7 +295,6 @@ cc_defaults {
     ],
     auto_gen_config: true,
     require_root: true,
-    compile_multilib: "first",
 }
 
 cc_test {
@@ -294,8 +305,17 @@ cc_test {
     ],
     test_suites: [
         "vts",
-        "device-tests",
+        "general-tests",
     ],
+    compile_multilib: "both",
+    multilib: {
+        lib32: {
+            suffix: "32",
+        },
+        lib64: {
+            suffix: "64",
+        },
+    },
     test_options: {
         min_shipping_api_level: 30,
     },
@@ -311,11 +331,18 @@ cc_test {
         "-DLIBSNAPSHOT_TEST_VAB_LEGACY",
     ],
     test_suites: [
-        "device-tests",
+        "general-tests",
     ],
+    compile_multilib: "64",
     test_options: {
         // Legacy VAB launched in Android R.
         min_shipping_api_level: 30,
+        test_runner_options: [
+            {
+                name: "force-no-test-error",
+                value: "false",
+            },
+        ],
     },
 }
 
@@ -345,6 +372,7 @@ cc_binary {
     ],
     srcs: [
         "snapshotctl.cpp",
+        "scratch_super.cpp",
     ],
     static_libs: [
         "libbrotli",
@@ -414,7 +442,7 @@ cc_test {
         "libstorage_literals_headers",
     ],
     test_suites: [
-        "device-tests",
+        "general-tests",
     ],
     test_options: {
         min_shipping_api_level: 30,

fs_mgr/libsnapshot/android/snapshot/snapshot.proto

@@ -229,6 +229,10 @@ message SnapshotUpdateStatus {
 
     // Enable direct reads from source device
     bool o_direct = 12;
+
+    // Number of cow operations to be merged at once
+    uint32 cow_op_merge_size = 13;
+
 }
 
 // Next: 10

fs_mgr/libsnapshot/device_info.cpp

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 #include "device_info.h"
+#include "scratch_super.h"
 
 #include <android-base/logging.h>
 #include <fs_mgr.h>
@@ -37,8 +38,24 @@ constexpr bool kIsRecovery = true;
 constexpr bool kIsRecovery = false;
 #endif
 
+DeviceInfo::DeviceInfo() {
+    std::string scratch_device = android::snapshot::GetScratchOtaMetadataPartition();
+    if (!scratch_device.empty()) {
+        std::string scratch_metadata =
+                android::snapshot::MapScratchOtaMetadataPartition(scratch_device);
+        if (!scratch_metadata.empty()) {
+            SetMetadataDir(scratch_metadata);
+            SetTempMetadata();
+        }
+    }
+}
+
 std::string DeviceInfo::GetMetadataDir() const {
-    return "/metadata/ota"s;
+    return metadata_dir_;
+}
+
+void DeviceInfo::SetMetadataDir(const std::string& value) {
+    metadata_dir_ = value;
 }
 
 std::string DeviceInfo::GetSlotSuffix() const {
@@ -104,6 +121,24 @@ bool DeviceInfo::IsFirstStageInit() const {
     return first_stage_init_;
 }
 
+bool DeviceInfo::SetActiveBootSlot([[maybe_unused]] unsigned int slot) {
+#ifdef LIBSNAPSHOT_USE_HAL
+    if (!EnsureBootHal()) {
+        return false;
+    }
+
+    CommandResult result = boot_control_->SetActiveBootSlot(slot);
+    if (!result.success) {
+        LOG(ERROR) << "Error setting slot " << slot << " active: " << result.errMsg;
+        return false;
+    }
+    return true;
+#else
+    LOG(ERROR) << "HAL support not enabled.";
+    return false;
+#endif
+}
+
 bool DeviceInfo::SetSlotAsUnbootable([[maybe_unused]] unsigned int slot) {
 #ifdef LIBSNAPSHOT_USE_HAL
     if (!EnsureBootHal()) {

fs_mgr/libsnapshot/device_info.h

@@ -29,6 +29,7 @@ class DeviceInfo final : public SnapshotManager::IDeviceInfo {
     using MergeStatus = ::aidl::android::hardware::boot::MergeStatus;
 
   public:
+    DeviceInfo();
     std::string GetMetadataDir() const override;
     std::string GetSlotSuffix() const override;
     std::string GetOtherSlotSuffix() const override;
@@ -36,19 +37,25 @@ class DeviceInfo final : public SnapshotManager::IDeviceInfo {
     std::string GetSuperDevice(uint32_t slot) const override;
     bool IsOverlayfsSetup() const override;
     bool SetBootControlMergeStatus(MergeStatus status) override;
+    bool SetActiveBootSlot(unsigned int slot) override;
     bool SetSlotAsUnbootable(unsigned int slot) override;
     bool IsRecovery() const override;
     std::unique_ptr<IImageManager> OpenImageManager() const override;
     bool IsFirstStageInit() const override;
     android::dm::IDeviceMapper& GetDeviceMapper() override;
-
+    void SetMetadataDir(const std::string& value);
     void set_first_stage_init(bool value) { first_stage_init_ = value; }
+    bool IsTempMetadata() const override { return temp_metadata_; }
+    void SetTempMetadata() { temp_metadata_ = true; }
 
   private:
     bool EnsureBootHal();
 
     android::fs_mgr::PartitionOpener opener_;
     bool first_stage_init_ = false;
+    // Default value
+    std::string metadata_dir_ = "/metadata/ota";
+    bool temp_metadata_ = false;
 #ifdef LIBSNAPSHOT_USE_HAL
     std::unique_ptr<::android::hal::BootControlClient> boot_control_;
 #endif

fs_mgr/libsnapshot/include/libsnapshot/mock_device_info.h

@@ -29,6 +29,7 @@ class MockDeviceInfo : public SnapshotManager::IDeviceInfo {
     MOCK_METHOD(const android::fs_mgr::IPartitionOpener&, GetPartitionOpener, (), (const));
     MOCK_METHOD(bool, IsOverlayfsSetup, (), (const, override));
     MOCK_METHOD(bool, SetBootControlMergeStatus, (MergeStatus status), (override));
+    MOCK_METHOD(bool, SetActiveBootSlot, (unsigned int slot), (override));
     MOCK_METHOD(bool, SetSlotAsUnbootable, (unsigned int slot), (override));
     MOCK_METHOD(bool, IsRecovery, (), (const, override));
     MOCK_METHOD(bool, IsFirstStageInit, (), (const, override));

fs_mgr/libsnapshot/include/libsnapshot/snapshot.h

@@ -104,12 +104,14 @@ class ISnapshotManager {
         virtual const android::fs_mgr::IPartitionOpener& GetPartitionOpener() const = 0;
         virtual bool IsOverlayfsSetup() const = 0;
         virtual bool SetBootControlMergeStatus(MergeStatus status) = 0;
+        virtual bool SetActiveBootSlot(unsigned int slot) = 0;
         virtual bool SetSlotAsUnbootable(unsigned int slot) = 0;
         virtual bool IsRecovery() const = 0;
         virtual bool IsTestDevice() const { return false; }
         virtual bool IsFirstStageInit() const = 0;
         virtual std::unique_ptr<IImageManager> OpenImageManager() const = 0;
         virtual android::dm::IDeviceMapper& GetDeviceMapper() = 0;
+        virtual bool IsTempMetadata() const = 0;
 
         // Helper method for implementing OpenImageManager.
         std::unique_ptr<IImageManager> OpenImageManager(const std::string& gsid_dir) const;
@@ -328,6 +330,10 @@ class SnapshotManager final : public ISnapshotManager {
     // might be needed to perform first-stage mounts.
     static bool IsSnapshotManagerNeeded();
 
+    // Map the temp OTA metadata partition from super
+    static bool MapTempOtaMetadataPartitionIfNeeded(
+            const std::function<bool(const std::string&)>& init);
+
     // Helper function for second stage init to restorecon on the rollback indicator.
     static std::string GetGlobalRollbackIndicatorPath();
 
@@ -675,6 +681,8 @@ class SnapshotManager final : public ISnapshotManager {
     std::string GetBootSnapshotsWithoutSlotSwitchPath();
     std::string GetSnapuserdFromSystemPath();
 
+    bool HasForwardMergeIndicator();
+
     const LpMetadata* ReadOldPartitionMetadata(LockedFile* lock);
 
     bool MapAllPartitions(LockedFile* lock, const std::string& super_device, uint32_t slot,
@@ -785,11 +793,8 @@ class SnapshotManager final : public ISnapshotManager {
     bool UpdateForwardMergeIndicator(bool wipe);
 
     // Helper for HandleImminentDataWipe.
-    // Call ProcessUpdateState and handle states with special rules before data wipe. Specifically,
+    // Call ProcessUpdateState and handle states with special rules before data wipe.
-    // if |allow_forward_merge| and allow-forward-merge indicator exists, initiate merge if
+    UpdateState ProcessUpdateStateOnDataWipe(const std::function<bool()>& callback);
-    // necessary.
-    UpdateState 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,
@@ -831,6 +836,8 @@ class SnapshotManager final : public ISnapshotManager {
     // Check if direct reads are enabled for the source image
     bool UpdateUsesODirect(LockedFile* lock);
 
+    // Get value of maximum cow op merge size
+    uint32_t GetUpdateCowOpMergeSize(LockedFile* lock);
     // Wrapper around libdm, with diagnostics.
     bool DeleteDeviceIfExists(const std::string& name,
                               const std::chrono::milliseconds& timeout_ms = {});
@@ -846,7 +853,6 @@ class SnapshotManager final : public ISnapshotManager {
     std::string metadata_dir_;
     std::unique_ptr<IImageManager> images_;
     bool use_first_stage_snapuserd_ = false;
-    bool in_factory_data_reset_ = false;
     std::function<bool(const std::string&)> uevent_regen_callback_;
     std::unique_ptr<SnapuserdClient> snapuserd_client_;
     std::unique_ptr<LpMetadata> old_partition_metadata_;

fs_mgr/libsnapshot/include_test/libsnapshot/test_helpers.h

@@ -30,6 +30,8 @@
 #include <storage_literals/storage_literals.h>
 #include <update_engine/update_metadata.pb.h>
 
+#include "utility.h"
+
 namespace android {
 namespace snapshot {
 
@@ -77,7 +79,7 @@ class TestDeviceInfo : public SnapshotManager::IDeviceInfo {
         : TestDeviceInfo(fake_super) {
         set_slot_suffix(slot_suffix);
     }
-    std::string GetMetadataDir() const override { return "/metadata/ota/test"s; }
+    std::string GetMetadataDir() const override { return metadata_dir_; }
     std::string GetSlotSuffix() const override { return slot_suffix_; }
     std::string GetOtherSlotSuffix() const override { return slot_suffix_ == "_a" ? "_b" : "_a"; }
     std::string GetSuperDevice([[maybe_unused]] uint32_t slot) const override { return "super"; }
@@ -90,6 +92,7 @@ class TestDeviceInfo : public SnapshotManager::IDeviceInfo {
     }
     bool IsOverlayfsSetup() const override { return false; }
     bool IsRecovery() const override { return recovery_; }
+    bool SetActiveBootSlot([[maybe_unused]] unsigned int slot) override { return true; }
     bool SetSlotAsUnbootable(unsigned int slot) override {
         unbootable_slots_.insert(slot);
         return true;
@@ -117,6 +120,7 @@ class TestDeviceInfo : public SnapshotManager::IDeviceInfo {
     void set_dm(android::dm::IDeviceMapper* dm) { dm_ = dm; }
 
     MergeStatus merge_status() const { return merge_status_; }
+    bool IsTempMetadata() const override { return temp_metadata_; }
 
   private:
     std::string slot_suffix_ = "_a";
@@ -126,6 +130,8 @@ class TestDeviceInfo : public SnapshotManager::IDeviceInfo {
     bool first_stage_init_ = false;
     std::unordered_set<uint32_t> unbootable_slots_;
     android::dm::IDeviceMapper* dm_ = nullptr;
+    std::string metadata_dir_ = "/metadata/ota/test";
+    bool temp_metadata_ = false;
 };
 
 class DeviceMapperWrapper : public android::dm::IDeviceMapper {
@@ -234,5 +240,21 @@ bool IsVirtualAbEnabled();
 
 #define RETURN_IF_NON_VIRTUAL_AB() RETURN_IF_NON_VIRTUAL_AB_MSG("")
 
+#define SKIP_IF_VENDOR_ON_ANDROID_S()                                        \
+    do {                                                                     \
+        if (IsVendorFromAndroid12())                                         \
+            GTEST_SKIP() << "Skip test as Vendor partition is on Android S"; \
+    } while (0)
+
+#define RETURN_IF_VENDOR_ON_ANDROID_S_MSG(msg) \
+    do {                                       \
+        if (IsVendorFromAndroid12()) {         \
+            std::cerr << (msg);                \
+            return;                            \
+        }                                      \
+    } while (0)
+
+#define RETURN_IF_VENDOR_ON_ANDROID_S() RETURN_IF_VENDOR_ON_ANDROID_S_MSG("")
+
 }  // namespace snapshot
 }  // namespace android

fs_mgr/libsnapshot/libsnapshot_cow/writer_v3.h

@@ -82,7 +82,7 @@ class CowWriterV3 : public CowWriterBase {
                                                  CowOperationType type);
     size_t GetCompressionFactor(const size_t blocks_to_compress, CowOperationType type) const;
 
-    constexpr bool IsBlockAligned(const size_t size) {
+    constexpr bool IsBlockAligned(const uint64_t size) {
         // These are the only block size supported. Block size beyond 256k
         // may impact random read performance post OTA boot.
         const size_t values[] = {4_KiB, 8_KiB, 16_KiB, 32_KiB, 64_KiB, 128_KiB, 256_KiB};

fs_mgr/libsnapshot/partition_cow_creator_test.cpp

@@ -250,8 +250,8 @@ TEST_F(PartitionCowCreatorTest, CompressionEnabled) {
                                 .target_partition = system_b,
                                 .current_metadata = builder_a.get(),
                                 .current_suffix = "_a",
-                                .using_snapuserd = true,
+                                .update = &update,
-                                .update = &update};
+                                .using_snapuserd = true};
 
     auto ret = creator.Run();
     ASSERT_TRUE(ret.has_value());
@@ -276,8 +276,8 @@ TEST_F(PartitionCowCreatorTest, CompressionWithNoManifest) {
                                 .target_partition = system_b,
                                 .current_metadata = builder_a.get(),
                                 .current_suffix = "_a",
-                                .using_snapuserd = true,
+                                .update = nullptr,
-                                .update = nullptr};
+                                .using_snapuserd = true};
 
     auto ret = creator.Run();
     ASSERT_FALSE(ret.has_value());

fs_mgr/libsnapshot/scratch_super.cpp

@@ -0,0 +1,416 @@
+// Copyright (C) 2024 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 <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/fs.h>
+#include <selinux/selinux.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <sys/types.h>
+#include <sys/vfs.h>
+#include <unistd.h>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/macros.h>
+#include <android-base/properties.h>
+#include <android-base/scopeguard.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <ext4_utils/ext4_utils.h>
+
+#include <libsnapshot/snapshot.h>
+
+#include <fs_mgr.h>
+#include <fs_mgr_dm_linear.h>
+#include <fstab/fstab.h>
+#include <liblp/builder.h>
+#include <storage_literals/storage_literals.h>
+#include <algorithm>
+#include <filesystem>
+#include <memory>
+#include <optional>
+#include <string>
+#include <vector>
+
+#include "device_info.h"
+#include "scratch_super.h"
+
+using namespace std::literals;
+using namespace android::dm;
+using namespace android::fs_mgr;
+using namespace android::storage_literals;
+
+namespace android {
+namespace snapshot {
+
+static bool UmountScratch() {
+    auto ota_dir = std::string(kOtaMetadataMount) + "/" + "ota";
+    std::error_code ec;
+
+    if (std::filesystem::remove_all(ota_dir, ec) == static_cast<std::uintmax_t>(-1)) {
+        LOG(ERROR) << "Failed to remove OTA directory: " << ec.message();
+        return false;
+    }
+
+    if (umount(kOtaMetadataMount) != 0) {
+        PLOG(ERROR) << "UmountScratch failed";
+        return false;
+    }
+
+    LOG(INFO) << "umount scratch_super success";
+    return true;
+}
+
+bool CleanupScratchOtaMetadataIfPresent(const ISnapshotManager::IDeviceInfo* info) {
+    if (!UmountScratch()) {
+        return false;
+    }
+
+    std::unique_ptr<MetadataBuilder> builder;
+    const auto partition_name = android::base::Basename(kOtaMetadataMount);
+    const std::vector<int> slots = {0, 1};
+
+    if (info == nullptr) {
+        info = new android::snapshot::DeviceInfo();
+    }
+
+    std::string super_device;
+    if (info->IsTestDevice()) {
+        super_device = "super";
+    } else {
+        super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();
+    }
+    const auto& opener = info->GetPartitionOpener();
+    std::string slot_suffix = info->GetSlotSuffix();
+    // Walk both the slots and clean up metadata related to scratch space from
+    // both the slots.
+    for (auto slot : slots) {
+        std::unique_ptr<MetadataBuilder> builder = MetadataBuilder::New(opener, super_device, slot);
+        if (!builder) {
+            return false;
+        }
+
+        if (builder->FindPartition(partition_name) != nullptr) {
+            builder->RemovePartition(partition_name);
+            auto metadata = builder->Export();
+            if (!metadata) {
+                return false;
+            }
+            if (!UpdatePartitionTable(info->GetPartitionOpener(), super_device, *metadata.get(),
+                                      slot)) {
+                LOG(ERROR) << "UpdatePartitionTable failed for slot: " << slot;
+                return false;
+            }
+            if (DestroyLogicalPartition(partition_name)) {
+                LOG(INFO) << "CleanupScratchOtaMetadata success for slot: " << slot;
+            }
+        }
+    }
+
+    return true;
+}
+
+static bool SetupOTADirs() {
+    if (setfscreatecon(android::snapshot::kOtaMetadataFileContext)) {
+        PLOG(ERROR) << "setfscreatecon failed: " << android::snapshot::kOtaMetadataFileContext;
+        return false;
+    }
+    const auto ota_dir = std::string(kOtaMetadataMount) + "/" + "ota";
+    if (mkdir(ota_dir.c_str(), 0755) != 0 && errno != EEXIST) {
+        PLOG(ERROR) << "mkdir " << ota_dir;
+        return false;
+    }
+
+    const auto snapshot_dir = ota_dir + "/" + "snapshots";
+    if (mkdir(snapshot_dir.c_str(), 0755) != 0 && errno != EEXIST) {
+        PLOG(ERROR) << "mkdir " << snapshot_dir;
+        return false;
+    }
+    if (setfscreatecon(nullptr)) {
+        PLOG(ERROR) << "setfscreatecon null";
+        return false;
+    }
+    return true;
+}
+
+static bool MountScratch(const std::string& device_path) {
+    if (access(device_path.c_str(), R_OK | W_OK)) {
+        LOG(ERROR) << "Path does not exist or is not readwrite: " << device_path;
+        return false;
+    }
+
+    std::string filesystem_candidate;
+    if (fs_mgr_is_ext4(device_path)) {
+        filesystem_candidate = "ext4";
+    } else {
+        LOG(ERROR) << "Scratch partition is not ext4";
+        return false;
+    }
+    if (setfscreatecon(android::snapshot::kOtaMetadataFileContext)) {
+        PLOG(ERROR) << "setfscreatecon failed: " << android::snapshot::kOtaMetadataFileContext;
+        return false;
+    }
+    if (mkdir(kOtaMetadataMount, 0755) && (errno != EEXIST)) {
+        PLOG(ERROR) << "create " << kOtaMetadataMount;
+        return false;
+    }
+
+    android::fs_mgr::FstabEntry entry;
+    entry.blk_device = device_path;
+    entry.mount_point = kOtaMetadataMount;
+    entry.flags = MS_NOATIME;
+    entry.flags |= MS_SYNCHRONOUS;
+    entry.fs_options = "nodiscard";
+    fs_mgr_set_blk_ro(device_path, false);
+    entry.fs_mgr_flags.check = true;
+
+    bool mounted = false;
+    entry.fs_type = filesystem_candidate.c_str();
+    if (fs_mgr_do_mount_one(entry) == 0) {
+        mounted = true;
+    }
+
+    if (setfscreatecon(nullptr)) {
+        PLOG(ERROR) << "setfscreatecon null";
+        return false;
+    }
+    if (!mounted) {
+        rmdir(kOtaMetadataMount);
+        return false;
+    }
+
+    return true;
+}
+
+static bool MakeScratchFilesystem(const std::string& scratch_device) {
+    std::string fs_type;
+    std::string command;
+    if (!access(kMkExt4, X_OK)) {
+        fs_type = "ext4";
+        command = kMkExt4 + " -F -b 4096 -t ext4 -m 0 -O has_journal -M "s + kOtaMetadataMount;
+    } else {
+        LOG(ERROR) << "No supported mkfs command or filesystem driver available, supported "
+                      "filesystems "
+                      "are: f2fs, ext4";
+        return false;
+    }
+    command += " " + scratch_device + " >/dev/null 2>/dev/null </dev/null";
+    fs_mgr_set_blk_ro(scratch_device, false);
+    auto ret = system(command.c_str());
+    if (ret) {
+        LOG(ERROR) << "make " << fs_type << " filesystem on " << scratch_device
+                   << " return=" << ret;
+        return false;
+    }
+    return true;
+}
+
+static bool CreateDynamicScratch(const ISnapshotManager::IDeviceInfo* info,
+                                 std::string* scratch_device) {
+    const auto partition_name = android::base::Basename(kOtaMetadataMount);
+    auto& dm = DeviceMapper::Instance();
+    if (info == nullptr) {
+        info = new android::snapshot::DeviceInfo();
+    }
+
+    std::string super_device;
+    if (info->IsTestDevice()) {
+        super_device = "super";
+    } else {
+        super_device = kPhysicalDevice + fs_mgr_get_super_partition_name();
+    }
+
+    bool partition_exists = dm.GetState(partition_name) != DmDeviceState::INVALID;
+    if (partition_exists) {
+        LOG(ERROR) << "Partition already exists: " << partition_name;
+        return false;
+    }
+
+    const auto& opener = info->GetPartitionOpener();
+    std::string slot_suffix = info->GetSlotSuffix();
+    int slot = SlotNumberForSlotSuffix(slot_suffix);
+    std::unique_ptr<MetadataBuilder> builder = MetadataBuilder::New(opener, super_device, slot);
+
+    if (!builder) {
+        LOG(ERROR) << "open " << super_device << " failed";
+        return false;
+    }
+
+    auto partition = builder->FindPartition(partition_name);
+    partition_exists = partition != nullptr;
+    if (partition_exists) {
+        LOG(ERROR) << "Partition exists in super metadata";
+        return false;
+    }
+
+    partition = builder->AddPartition(partition_name, LP_PARTITION_ATTR_NONE);
+    if (!partition) {
+        LOG(ERROR) << "AddPartition failed " << partition_name;
+        return false;
+    }
+
+    auto free_space = builder->AllocatableSpace() - builder->UsedSpace();
+    if (free_space < kOtaMetadataPartitionSize) {
+        LOG(ERROR) << "No space in super partition. Free space: " << free_space
+                   << " Requested space: " << kOtaMetadataPartitionSize;
+        return false;
+    }
+
+    LOG(INFO) << "CreateDynamicScratch: free_space: " << free_space
+              << " scratch_size: " << kOtaMetadataPartitionSize << " slot_number: " << slot;
+
+    if (!builder->ResizePartition(partition, kOtaMetadataPartitionSize)) {
+        LOG(ERROR) << "ResizePartition failed: " << partition_name << " free_space: " << free_space
+                   << " scratch_size: " << kOtaMetadataPartitionSize;
+        return false;
+    }
+
+    auto metadata = builder->Export();
+    CreateLogicalPartitionParams params;
+
+    if (!metadata ||
+        !UpdatePartitionTable(info->GetPartitionOpener(), super_device, *metadata.get(), slot)) {
+        LOG(ERROR) << "UpdatePartitionTable failed: " << partition_name;
+        return false;
+    }
+    params = {
+            .block_device = super_device,
+            .metadata_slot = slot,
+            .partition_name = partition_name,
+            .force_writable = true,
+            .timeout_ms = 10s,
+            .partition_opener = &info->GetPartitionOpener(),
+    };
+
+    if (!CreateLogicalPartition(params, scratch_device)) {
+        LOG(ERROR) << "CreateLogicalPartition failed";
+        return false;
+    }
+
+    LOG(INFO) << "Scratch device created successfully: " << *scratch_device << " slot: " << slot;
+    return true;
+}
+
+bool IsScratchOtaMetadataOnSuper() {
+    auto partition_name = android::base::Basename(kOtaMetadataMount);
+    auto source_slot = fs_mgr_get_slot_suffix();
+    auto source_slot_number = SlotNumberForSlotSuffix(source_slot);
+
+    const auto super_device =
+            kPhysicalDevice + fs_mgr_get_super_partition_name(!source_slot_number);
+
+    auto metadata = android::fs_mgr::ReadMetadata(super_device, !source_slot_number);
+    if (!metadata) {
+        return false;
+    }
+    auto partition = android::fs_mgr::FindPartition(*metadata.get(), partition_name);
+    if (!partition) {
+        return false;
+    }
+
+    auto& dm = DeviceMapper::Instance();
+    if (dm.GetState(partition_name) == DmDeviceState::ACTIVE) {
+        LOG(INFO) << "Partition: " << partition_name << " is active";
+        return true;
+    }
+
+    CreateLogicalPartitionParams params = {
+            .block_device = super_device,
+            .metadata = metadata.get(),
+            .partition = partition,
+    };
+
+    std::string scratch_path;
+    if (!CreateLogicalPartition(params, &scratch_path)) {
+        LOG(ERROR) << "Could not create logical partition: " << partition_name;
+        return false;
+    }
+    LOG(INFO) << "Scratch device: " << scratch_path << " created successfully";
+
+    return true;
+}
+
+std::string GetScratchOtaMetadataPartition() {
+    std::string device;
+    auto& dm = DeviceMapper::Instance();
+    auto partition_name = android::base::Basename(kOtaMetadataMount);
+
+    bool invalid_partition = (dm.GetState(partition_name) == DmDeviceState::INVALID);
+    if (!invalid_partition && dm.GetDmDevicePathByName(partition_name, &device)) {
+        return device;
+    }
+    return "";
+}
+
+static bool ScratchAlreadyMounted(const std::string& mount_point) {
+    android::fs_mgr::Fstab fstab;
+    if (!ReadFstabFromProcMounts(&fstab)) {
+        return false;
+    }
+    for (const auto& entry : GetEntriesForMountPoint(&fstab, mount_point)) {
+        if (entry->fs_type == "ext4") {
+            return true;
+        }
+    }
+    return false;
+}
+
+std::string MapScratchOtaMetadataPartition(const std::string& scratch_device) {
+    if (!ScratchAlreadyMounted(kOtaMetadataMount)) {
+        if (!MountScratch(scratch_device)) {
+            return "";
+        }
+    }
+
+    auto ota_dir = std::string(kOtaMetadataMount) + "/" + "ota";
+    if (access(ota_dir.c_str(), F_OK) != 0) {
+        return "";
+    }
+    return ota_dir;
+}
+
+// Entry point to create a scratch device on super partition
+// This will create a 1MB space in super. The space will be
+// from the current active slot. Ext4 filesystem will be created
+// on this scratch device and all the OTA related directories
+// will be created.
+bool CreateScratchOtaMetadataOnSuper(const ISnapshotManager::IDeviceInfo* info) {
+    std::string scratch_device;
+
+    if (!CreateDynamicScratch(info, &scratch_device)) {
+        LOG(ERROR) << "CreateDynamicScratch failed";
+        return false;
+    }
+    if (!MakeScratchFilesystem(scratch_device)) {
+        LOG(ERROR) << "MakeScratchFilesystem failed";
+        return false;
+    }
+    if (!MountScratch(scratch_device)) {
+        LOG(ERROR) << "MountScratch failed";
+        return false;
+    }
+    if (!SetupOTADirs()) {
+        LOG(ERROR) << "SetupOTADirs failed";
+        return false;
+    }
+    return true;
+}
+
+}  // namespace snapshot
+}  // namespace android

fs_mgr/libsnapshot/scratch_super.h

@@ -0,0 +1,33 @@
+// Copyright (C) 2024 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
+
+namespace android {
+namespace snapshot {
+
+constexpr char kMkExt4[] = "/system/bin/mke2fs";
+constexpr char kOtaMetadataFileContext[] = "u:object_r:ota_metadata_file:s0";
+constexpr char kOtaMetadataMount[] = "/mnt/scratch_ota_metadata_super";
+const size_t kOtaMetadataPartitionSize = uint64_t(1 * 1024 * 1024);
+constexpr char kPhysicalDevice[] = "/dev/block/by-name/";
+
+bool IsScratchOtaMetadataOnSuper();
+std::string GetScratchOtaMetadataPartition();
+std::string MapScratchOtaMetadataPartition(const std::string& device);
+bool CreateScratchOtaMetadataOnSuper(const ISnapshotManager::IDeviceInfo* info = nullptr);
+bool CleanupScratchOtaMetadataIfPresent(const ISnapshotManager::IDeviceInfo* info = nullptr);
+
+}  // namespace snapshot
+}  // namespace android

fs_mgr/libsnapshot/snapshot.cpp

@@ -22,6 +22,7 @@
 #include <sys/unistd.h>
 #include <sys/xattr.h>
 
+#include <chrono>
 #include <filesystem>
 #include <optional>
 #include <thread>
@@ -47,6 +48,7 @@
 #include <libsnapshot/snapshot_stats.h>
 #include "device_info.h"
 #include "partition_cow_creator.h"
+#include "scratch_super.h"
 #include "snapshot_metadata_updater.h"
 #include "utility.h"
 
@@ -116,7 +118,11 @@ std::unique_ptr<SnapshotManager> SnapshotManager::New(IDeviceInfo* info) {
         info = new DeviceInfo();
     }
 
-    return std::unique_ptr<SnapshotManager>(new SnapshotManager(info));
+    auto sm = std::unique_ptr<SnapshotManager>(new SnapshotManager(info));
+    if (info->IsTempMetadata()) {
+        LOG(INFO) << "Using temp metadata from super";
+    }
+    return sm;
 }
 
 std::unique_ptr<SnapshotManager> SnapshotManager::NewForFirstStageMount(IDeviceInfo* info) {
@@ -1109,6 +1115,13 @@ UpdateState SnapshotManager::ProcessUpdateState(const std::function<bool()>& cal
         if (result.state == UpdateState::MergeFailed) {
             AcknowledgeMergeFailure(result.failure_code);
         }
+
+        if (result.state == UpdateState::MergeCompleted) {
+            if (device_->IsTempMetadata()) {
+                CleanupScratchOtaMetadataIfPresent();
+            }
+        }
+
         if (result.state != UpdateState::Merging) {
             // Either there is no merge, or the merge was finished, so no need
             // to keep waiting.
@@ -1708,6 +1721,10 @@ bool SnapshotManager::PerformInitTransition(InitTransition transition,
         if (UpdateUsesODirect(lock.get())) {
             snapuserd_argv->emplace_back("-o_direct");
         }
+        uint cow_op_merge_size = GetUpdateCowOpMergeSize(lock.get());
+        if (cow_op_merge_size != 0) {
+            snapuserd_argv->emplace_back("-cow_op_merge_size=" + std::to_string(cow_op_merge_size));
+        }
     }
 
     size_t num_cows = 0;
@@ -2130,6 +2147,11 @@ bool SnapshotManager::UpdateUsesODirect(LockedFile* lock) {
     return update_status.o_direct();
 }
 
+uint32_t SnapshotManager::GetUpdateCowOpMergeSize(LockedFile* lock) {
+    SnapshotUpdateStatus update_status = ReadSnapshotUpdateStatus(lock);
+    return update_status.cow_op_merge_size();
+}
+
 bool SnapshotManager::MarkSnapuserdFromSystem() {
     auto path = GetSnapuserdFromSystemPath();
 
@@ -2300,7 +2322,27 @@ bool SnapshotManager::ListSnapshots(LockedFile* lock, std::vector<std::string>*
 }
 
 bool SnapshotManager::IsSnapshotManagerNeeded() {
-    return access(kBootIndicatorPath, F_OK) == 0;
+    if (access(kBootIndicatorPath, F_OK) == 0) {
+        return true;
+    }
+
+    if (IsScratchOtaMetadataOnSuper()) {
+        return true;
+    }
+
+    return false;
+}
+
+bool SnapshotManager::MapTempOtaMetadataPartitionIfNeeded(
+        const std::function<bool(const std::string&)>& init) {
+    auto device = android::snapshot::GetScratchOtaMetadataPartition();
+    if (!device.empty()) {
+        init(device);
+        if (android::snapshot::MapScratchOtaMetadataPartition(device).empty()) {
+            return false;
+        }
+    }
+    return true;
 }
 
 std::string SnapshotManager::GetGlobalRollbackIndicatorPath() {
@@ -2387,6 +2429,12 @@ bool SnapshotManager::MapAllPartitions(LockedFile* lock, const std::string& supe
             continue;
         }
 
+        if (GetPartitionName(partition) ==
+            android::base::Basename(android::snapshot::kOtaMetadataMount)) {
+            LOG(INFO) << "Partition: " << GetPartitionName(partition) << " skipping";
+            continue;
+        }
+
         CreateLogicalPartitionParams params = {
                 .block_device = super_device,
                 .metadata = metadata.get(),
@@ -2892,10 +2940,12 @@ bool SnapshotManager::UnmapAllSnapshots() {
 }
 
 bool SnapshotManager::UnmapAllSnapshots(LockedFile* lock) {
+    LOG(INFO) << "Lock acquired for " << __FUNCTION__;
     std::vector<std::string> snapshots;
     if (!ListSnapshots(lock, &snapshots)) {
         return false;
     }
+    LOG(INFO) << "Found " << snapshots.size() << " partitions with snapshots";
 
     for (const auto& snapshot : snapshots) {
         if (!UnmapPartitionWithSnapshot(lock, snapshot)) {
@@ -2903,6 +2953,7 @@ bool SnapshotManager::UnmapAllSnapshots(LockedFile* lock) {
             return false;
         }
     }
+    LOG(INFO) << "Unmapped " << snapshots.size() << " partitions with snapshots";
 
     // Terminate the daemon and release the snapuserd_client_ object.
     // If we need to re-connect with the daemon, EnsureSnapuserdConnected()
@@ -2918,6 +2969,7 @@ bool SnapshotManager::UnmapAllSnapshots(LockedFile* lock) {
 
 auto SnapshotManager::OpenFile(const std::string& file,
                                int lock_flags) -> std::unique_ptr<LockedFile> {
+    const auto start = std::chrono::system_clock::now();
     unique_fd fd(open(file.c_str(), O_RDONLY | O_CLOEXEC | O_NOFOLLOW));
     if (fd < 0) {
         PLOG(ERROR) << "Open failed: " << file;
@@ -2930,6 +2982,11 @@ auto SnapshotManager::OpenFile(const std::string& file,
     // For simplicity, we want to CHECK that lock_mode == LOCK_EX, in some
     // calls, so strip extra flags.
     int lock_mode = lock_flags & (LOCK_EX | LOCK_SH);
+    const auto end = std::chrono::system_clock::now();
+    const auto duration_ms = std::chrono::duration_cast<std::chrono::milliseconds>(end - start);
+    if (duration_ms >= 1000ms) {
+        LOG(INFO) << "Taking lock on " << file << " took " << duration_ms.count() << "ms";
+    }
     return std::make_unique<LockedFile>(file, std::move(fd), lock_mode);
 }
 
@@ -3082,6 +3139,7 @@ bool SnapshotManager::WriteUpdateState(LockedFile* lock, UpdateState state,
         status.set_io_uring_enabled(old_status.io_uring_enabled());
         status.set_legacy_snapuserd(old_status.legacy_snapuserd());
         status.set_o_direct(old_status.o_direct());
+        status.set_cow_op_merge_size(old_status.cow_op_merge_size());
     }
     return WriteSnapshotUpdateStatus(lock, status);
 }
@@ -3464,6 +3522,8 @@ Return SnapshotManager::CreateUpdateSnapshots(const DeltaArchiveManifest& manife
             status.set_legacy_snapuserd(true);
             LOG(INFO) << "Setting legacy_snapuserd to true";
         }
+        status.set_cow_op_merge_size(
+                android::base::GetUintProperty<uint32_t>("ro.virtual_ab.cow_op_merge_size", 0));
     } else if (legacy_compression) {
         LOG(INFO) << "Virtual A/B using legacy snapuserd";
     } else {
@@ -3899,6 +3959,7 @@ bool SnapshotManager::Dump(std::ostream& os) {
     ss << "Using userspace snapshots: " << update_status.userspace_snapshots() << std::endl;
     ss << "Using io_uring: " << update_status.io_uring_enabled() << std::endl;
     ss << "Using o_direct: " << update_status.o_direct() << std::endl;
+    ss << "Cow op merge size (0 for uncapped): " << update_status.cow_op_merge_size() << std::endl;
     ss << "Using XOR compression: " << GetXorCompressionEnabledProperty() << std::endl;
     ss << "Current slot: " << device_->GetSlotSuffix() << std::endl;
     ss << "Boot indicator: booting from " << GetCurrentSlot() << " slot" << std::endl;
@@ -3982,44 +4043,90 @@ bool SnapshotManager::HandleImminentDataWipe(const std::function<void()>& callba
         // We allow the wipe to continue, because if we can't mount /metadata,
         // it is unlikely the device would have booted anyway. If there is no
         // metadata partition, then the device predates Virtual A/B.
+        LOG(INFO) << "/metadata not found; allowing wipe.";
         return true;
     }
 
-    // Check this early, so we don't accidentally start trying to populate
+    // This could happen if /metadata mounted but there is no filesystem
-    // the state file in recovery. Note we don't call GetUpdateState since
+    // structure. Weird, but we have to assume there's no OTA pending, and
-    // we want errors in acquiring the lock to be propagated, instead of
+    // thus we let the wipe proceed.
-    // returning UpdateState::None.
+    UpdateState state;
-    auto state_file = GetStateFilePath();
+    {
-    if (access(state_file.c_str(), F_OK) != 0 && errno == ENOENT) {
+        auto lock = LockExclusive();
-        return true;
+        if (!lock) {
-    }
+            LOG(ERROR) << "Unable to determine update state; allowing wipe.";
-
+            return true;
-    auto slot_number = SlotNumberForSlotSuffix(device_->GetSlotSuffix());
-    auto super_path = device_->GetSuperDevice(slot_number);
-    if (!CreateLogicalAndSnapshotPartitions(super_path, 20s)) {
-        LOG(ERROR) << "Unable to map partitions to complete merge.";
-        return false;
-    }
-
-    auto process_callback = [&]() -> bool {
-        if (callback) {
-            callback();
         }
-        return true;
-    };
 
-    in_factory_data_reset_ = true;
+        state = ReadUpdateState(lock.get());
-    UpdateState state =
+        LOG(INFO) << "Update state before wipe: " << state << "; slot: " << GetCurrentSlot()
-            ProcessUpdateStateOnDataWipe(true /* allow_forward_merge */, process_callback);
+                  << "; suffix: " << device_->GetSlotSuffix();
-    in_factory_data_reset_ = false;
-
-    if (state == UpdateState::MergeFailed) {
-        return false;
     }
 
-    // Nothing should be depending on partitions now, so unmap them all.
+    bool try_merge = false;
-    if (!UnmapAllPartitionsInRecovery()) {
+    switch (state) {
-        LOG(ERROR) << "Unable to unmap all partitions; fastboot may fail to flash.";
+        case UpdateState::None:
+        case UpdateState::Initiated:
+            LOG(INFO) << "Wipe is not impacted by update state; allowing wipe.";
+            break;
+        case UpdateState::Unverified:
+            if (GetCurrentSlot() != Slot::Target) {
+                LOG(INFO) << "Wipe is not impacted by rolled back update; allowing wipe";
+                break;
+            }
+            if (!HasForwardMergeIndicator()) {
+                auto slot_number = SlotNumberForSlotSuffix(device_->GetSlotSuffix());
+                auto other_slot_number = SlotNumberForSlotSuffix(device_->GetOtherSlotSuffix());
+
+                // We're not allowed to forward merge, so forcefully rollback the
+                // slot switch.
+                LOG(INFO) << "Allowing wipe due to lack of forward merge indicator; reverting to "
+                             "old slot since update will be deleted.";
+                device_->SetSlotAsUnbootable(slot_number);
+                device_->SetActiveBootSlot(other_slot_number);
+                break;
+            }
+
+            // Forward merge indicator means we have to mount snapshots and try to merge.
+            LOG(INFO) << "Forward merge indicator is present.";
+            try_merge = true;
+            break;
+        case UpdateState::Merging:
+        case UpdateState::MergeFailed:
+            try_merge = true;
+            break;
+        case UpdateState::MergeNeedsReboot:
+        case UpdateState::Cancelled:
+            LOG(INFO) << "Unexpected update state in recovery; allowing wipe.";
+            break;
+        default:
+            break;
+    }
+
+    if (try_merge) {
+        auto slot_number = SlotNumberForSlotSuffix(device_->GetSlotSuffix());
+        auto super_path = device_->GetSuperDevice(slot_number);
+        if (!CreateLogicalAndSnapshotPartitions(super_path, 20s)) {
+            LOG(ERROR) << "Unable to map partitions to complete merge.";
+            return false;
+        }
+
+        auto process_callback = [&]() -> bool {
+            if (callback) {
+                callback();
+            }
+            return true;
+        };
+
+        state = ProcessUpdateStateOnDataWipe(process_callback);
+        if (state == UpdateState::MergeFailed) {
+            return false;
+        }
+
+        // Nothing should be depending on partitions now, so unmap them all.
+        if (!UnmapAllPartitionsInRecovery()) {
+            LOG(ERROR) << "Unable to unmap all partitions; fastboot may fail to flash.";
+        }
     }
 
     if (state != UpdateState::None) {
@@ -4065,58 +4172,40 @@ bool SnapshotManager::FinishMergeInRecovery() {
     return true;
 }
 
-UpdateState SnapshotManager::ProcessUpdateStateOnDataWipe(bool allow_forward_merge,
+UpdateState SnapshotManager::ProcessUpdateStateOnDataWipe(const std::function<bool()>& callback) {
-                                                          const std::function<bool()>& callback) {
+    while (true) {
-    auto slot_number = SlotNumberForSlotSuffix(device_->GetSlotSuffix());
+        UpdateState state = ProcessUpdateState(callback);
-    UpdateState state = ProcessUpdateState(callback);
+        LOG(INFO) << "Processed updated state in recovery: " << state;
-    LOG(INFO) << "Update state in recovery: " << state;
+        switch (state) {
-    switch (state) {
+            case UpdateState::MergeFailed:
-        case UpdateState::MergeFailed:
+                LOG(ERROR) << "Unrecoverable merge failure detected.";
-            LOG(ERROR) << "Unrecoverable merge failure detected.";
+                return state;
-            return state;
+            case UpdateState::Unverified: {
-        case UpdateState::Unverified: {
+                // Unverified was already handled earlier, in HandleImminentDataWipe,
-            // If an OTA was just applied but has not yet started merging:
+                // but it will fall through here if a forward merge is required.
-            //
+                //
-            // - if forward merge is allowed, initiate merge and call
+                // If InitiateMerge fails, we early return. If it succeeds, then we
-            // ProcessUpdateState again.
+                // are guaranteed that the next call to ProcessUpdateState will not
-            //
+                // return Unverified.
-            // - if forward merge is not allowed, we
+                if (!InitiateMerge()) {
-            // have no choice but to revert slots, because the current slot will
+                    LOG(ERROR) << "Failed to initiate merge on data wipe.";
-            // immediately become unbootable. Rather than wait for the device
+                    return UpdateState::MergeFailed;
-            // to reboot N times until a rollback, we proactively disable the
-            // new slot instead.
-            //
-            // Since the rollback is inevitable, we don't treat a HAL failure
-            // as an error here.
-            auto slot = GetCurrentSlot();
-            if (slot == Slot::Target) {
-                if (allow_forward_merge &&
-                    access(GetForwardMergeIndicatorPath().c_str(), F_OK) == 0) {
-                    LOG(INFO) << "Forward merge allowed, initiating merge now.";
-
-                    if (!InitiateMerge()) {
-                        LOG(ERROR) << "Failed to initiate merge on data wipe.";
-                        return UpdateState::MergeFailed;
-                    }
-                    return ProcessUpdateStateOnDataWipe(false /* allow_forward_merge */, callback);
                 }
-
+                continue;
-                LOG(ERROR) << "Reverting to old slot since update will be deleted.";
-                device_->SetSlotAsUnbootable(slot_number);
-            } else {
-                LOG(INFO) << "Booting from " << slot << " slot, no action is taken.";
             }
-            break;
+            case UpdateState::MergeNeedsReboot:
+                // We shouldn't get here, because nothing is depending on
+                // logical partitions.
+                LOG(ERROR) << "Unexpected merge-needs-reboot state in recovery.";
+                return state;
+            default:
+                return state;
         }
-        case UpdateState::MergeNeedsReboot:
-            // We shouldn't get here, because nothing is depending on
-            // logical partitions.
-            LOG(ERROR) << "Unexpected merge-needs-reboot state in recovery.";
-            break;
-        default:
-            break;
     }
-    return state;
+}
+
+bool SnapshotManager::HasForwardMergeIndicator() {
+    return access(GetForwardMergeIndicatorPath().c_str(), F_OK) == 0;
 }
 
 bool SnapshotManager::EnsureNoOverflowSnapshot(LockedFile* lock) {

fs_mgr/libsnapshot/snapshot_stats.cpp

@@ -25,7 +25,7 @@ namespace snapshot {
 
 SnapshotMergeStats* SnapshotMergeStats::GetInstance(SnapshotManager& parent) {
     static SnapshotMergeStats g_instance(parent.GetMergeStateFilePath());
-    CHECK(g_instance.path_ == parent.GetMergeStateFilePath());
+    CHECK_EQ(g_instance.path_, parent.GetMergeStateFilePath());
     return &g_instance;
 }
 

fs_mgr/libsnapshot/snapshot_test.cpp

@@ -47,6 +47,7 @@
 #include <android/snapshot/snapshot.pb.h>
 #include <libsnapshot/test_helpers.h>
 #include "partition_cow_creator.h"
+#include "scratch_super.h"
 #include "utility.h"
 
 // Mock classes are not used. Header included to ensure mocked class definition aligns with the
@@ -122,6 +123,7 @@ class SnapshotTest : public ::testing::Test {
         LOG(INFO) << "Starting test: " << test_name_;
 
         SKIP_IF_NON_VIRTUAL_AB();
+        SKIP_IF_VENDOR_ON_ANDROID_S();
 
         SetupProperties();
         if (!DeviceSupportsMode()) {
@@ -168,6 +170,7 @@ class SnapshotTest : public ::testing::Test {
 
     void TearDown() override {
         RETURN_IF_NON_VIRTUAL_AB();
+        RETURN_IF_VENDOR_ON_ANDROID_S();
 
         LOG(INFO) << "Tearing down SnapshotTest test: " << test_name_;
 
@@ -1015,6 +1018,7 @@ class SnapshotUpdateTest : public SnapshotTest {
   public:
     void SetUp() override {
         SKIP_IF_NON_VIRTUAL_AB();
+        SKIP_IF_VENDOR_ON_ANDROID_S();
 
         SnapshotTest::SetUp();
         if (!image_manager_) {
@@ -1097,6 +1101,7 @@ class SnapshotUpdateTest : public SnapshotTest {
     }
     void TearDown() override {
         RETURN_IF_NON_VIRTUAL_AB();
+        RETURN_IF_VENDOR_ON_ANDROID_S();
 
         LOG(INFO) << "Tearing down SnapshotUpdateTest test: " << test_name_;
 
@@ -1338,6 +1343,15 @@ class SnapshotUpdateTest : public SnapshotTest {
     DynamicPartitionGroup* group_ = nullptr;
 };
 
+TEST_F(SnapshotUpdateTest, SuperOtaMetadataTest) {
+    auto info = new TestDeviceInfo(fake_super);
+    ASSERT_TRUE(CreateScratchOtaMetadataOnSuper(info));
+    std::string scratch_device = GetScratchOtaMetadataPartition();
+    ASSERT_NE(scratch_device, "");
+    ASSERT_NE(MapScratchOtaMetadataPartition(scratch_device), "");
+    ASSERT_TRUE(CleanupScratchOtaMetadataIfPresent(info));
+}
+
 // Test full update flow executed by update_engine. Some partitions uses super empty space,
 // some uses images, and some uses both.
 // Also test UnmapUpdateSnapshot unmaps everything.
@@ -1978,6 +1992,8 @@ TEST_F(MetadataMountedTest, Android) {
 }
 
 TEST_F(MetadataMountedTest, Recovery) {
+    GTEST_SKIP() << "b/350715463";
+
     test_device->set_recovery(true);
     metadata_dir_ = test_device->GetMetadataDir();
 
@@ -2096,10 +2112,10 @@ TEST_F(SnapshotUpdateTest, DataWipeRollbackInRecovery) {
     test_device->set_recovery(true);
     auto new_sm = NewManagerForFirstStageMount(test_device);
 
+    EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::Unverified);
     ASSERT_TRUE(new_sm->HandleImminentDataWipe());
     // Manually mount metadata so that we can call GetUpdateState() below.
     MountMetadata();
-    EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::None);
     EXPECT_TRUE(test_device->IsSlotUnbootable(1));
     EXPECT_FALSE(test_device->IsSlotUnbootable(0));
 }
@@ -2121,6 +2137,7 @@ TEST_F(SnapshotUpdateTest, DataWipeAfterRollback) {
     test_device->set_recovery(true);
     auto new_sm = NewManagerForFirstStageMount(test_device);
 
+    EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::Unverified);
     ASSERT_TRUE(new_sm->HandleImminentDataWipe());
     EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::None);
     EXPECT_FALSE(test_device->IsSlotUnbootable(0));
@@ -2129,10 +2146,6 @@ TEST_F(SnapshotUpdateTest, DataWipeAfterRollback) {
 
 // Test update package that requests data wipe.
 TEST_F(SnapshotUpdateTest, DataWipeRequiredInPackage) {
-    if (ShouldSkipLegacyMerging()) {
-        GTEST_SKIP() << "Skipping legacy merge in test";
-    }
-
     AddOperationForPartitions();
     // Execute the update.
     ASSERT_TRUE(sm->BeginUpdate());
@@ -2151,6 +2164,7 @@ TEST_F(SnapshotUpdateTest, DataWipeRequiredInPackage) {
     test_device->set_recovery(true);
     auto new_sm = NewManagerForFirstStageMount(test_device);
 
+    EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::Unverified);
     ASSERT_TRUE(new_sm->HandleImminentDataWipe());
     // Manually mount metadata so that we can call GetUpdateState() below.
     MountMetadata();
@@ -2172,10 +2186,6 @@ TEST_F(SnapshotUpdateTest, DataWipeRequiredInPackage) {
 
 // Test update package that requests data wipe.
 TEST_F(SnapshotUpdateTest, DataWipeWithStaleSnapshots) {
-    if (ShouldSkipLegacyMerging()) {
-        GTEST_SKIP() << "Skipping legacy merge in test";
-    }
-
     AddOperationForPartitions();
 
     // Execute the update.
@@ -2216,6 +2226,7 @@ TEST_F(SnapshotUpdateTest, DataWipeWithStaleSnapshots) {
     test_device->set_recovery(true);
     auto new_sm = NewManagerForFirstStageMount(test_device);
 
+    EXPECT_EQ(new_sm->GetUpdateState(), UpdateState::Unverified);
     ASSERT_TRUE(new_sm->HandleImminentDataWipe());
     // Manually mount metadata so that we can call GetUpdateState() below.
     MountMetadata();
@@ -2659,6 +2670,7 @@ TEST_F(SnapshotTest, FlagCheck) {
     status.set_o_direct(true);
     status.set_io_uring_enabled(true);
     status.set_userspace_snapshots(true);
+    status.set_cow_op_merge_size(16);
 
     sm->WriteSnapshotUpdateStatus(lock_.get(), status);
     // Ensure a connection to the second-stage daemon, but use the first-stage
@@ -2680,6 +2692,8 @@ TEST_F(SnapshotTest, FlagCheck) {
                 snapuserd_argv.end());
     ASSERT_TRUE(std::find(snapuserd_argv.begin(), snapuserd_argv.end(), "-user_snapshot") !=
                 snapuserd_argv.end());
+    ASSERT_TRUE(std::find(snapuserd_argv.begin(), snapuserd_argv.end(), "-cow_op_merge_size=16") !=
+                snapuserd_argv.end());
 }
 
 class FlashAfterUpdateTest : public SnapshotUpdateTest,
@@ -2885,6 +2899,8 @@ void SnapshotTestEnvironment::SetUp() {
 
 void SnapshotTestEnvironment::TearDown() {
     RETURN_IF_NON_VIRTUAL_AB();
+    RETURN_IF_VENDOR_ON_ANDROID_S();
+
     if (super_images_ != nullptr) {
         DeleteBackingImage(super_images_.get(), "fake-super");
     }

fs_mgr/libsnapshot/snapshotctl.cpp

@@ -16,7 +16,6 @@
 
 #include <sysexits.h>
 #include <unistd.h>
-
 #include <chrono>
 #include <filesystem>
 #include <fstream>
@@ -46,6 +45,7 @@
 #include <storage_literals/storage_literals.h>
 
 #include "partition_cow_creator.h"
+#include "scratch_super.h"
 
 #ifdef SNAPSHOTCTL_USERDEBUG_OR_ENG
 #include <BootControlClient.h>
@@ -57,6 +57,8 @@ using namespace android::storage_literals;
 using android::base::LogdLogger;
 using android::base::StderrLogger;
 using android::base::TeeLogger;
+using namespace android::dm;
+using namespace android::fs_mgr;
 using android::fs_mgr::CreateLogicalPartitionParams;
 using android::fs_mgr::FindPartition;
 using android::fs_mgr::GetPartitionSize;
@@ -97,7 +99,7 @@ namespace snapshot {
 #ifdef SNAPSHOTCTL_USERDEBUG_OR_ENG
 class MapSnapshots {
   public:
-    MapSnapshots(std::string path = "");
+    MapSnapshots(std::string path = "", bool metadata_super = false);
     bool CreateSnapshotDevice(std::string& partition_name, std::string& patch);
     bool InitiateThreadedSnapshotWrite(std::string& pname, std::string& snapshot_patch);
     bool FinishSnapshotWrites();
@@ -122,15 +124,12 @@ class MapSnapshots {
 
     std::vector<std::string> patchfiles_;
     chromeos_update_engine::DeltaArchiveManifest manifest_;
+    bool metadata_super_ = false;
 };
 
-MapSnapshots::MapSnapshots(std::string path) {
+MapSnapshots::MapSnapshots(std::string path, bool metadata_super) {
-    sm_ = SnapshotManager::New();
-    if (!sm_) {
-        std::cout << "Failed to create snapshotmanager";
-        exit(1);
-    }
     snapshot_dir_path_ = path + "/";
+    metadata_super_ = metadata_super;
 }
 
 std::string MapSnapshots::GetGroupName(const android::fs_mgr::LpMetadata& pt,
@@ -150,6 +149,12 @@ std::string MapSnapshots::GetGroupName(const android::fs_mgr::LpMetadata& pt,
 }
 
 bool MapSnapshots::PrepareUpdate() {
+    if (metadata_super_ && !CreateScratchOtaMetadataOnSuper()) {
+        LOG(ERROR) << "Failed to create OTA metadata on super";
+        return false;
+    }
+    sm_ = SnapshotManager::New();
+
     auto source_slot = fs_mgr_get_slot_suffix();
     auto source_slot_number = SlotNumberForSlotSuffix(source_slot);
     auto super_source = fs_mgr_get_super_partition_name(source_slot_number);
@@ -234,7 +239,17 @@ bool MapSnapshots::PrepareUpdate() {
 
 bool MapSnapshots::GetCowDevicePath(std::string partition_name, std::string* cow_path) {
     auto& dm = android::dm::DeviceMapper::Instance();
-    std::string cow_device = partition_name + "-cow";
+
+    std::string cow_device = partition_name + "-cow-img";
+    if (metadata_super_) {
+        // If COW device exists on /data, then data wipe cannot be done.
+        if (dm.GetDmDevicePathByName(cow_device, cow_path)) {
+            LOG(ERROR) << "COW device exists on /data: " << *cow_path;
+            return false;
+        }
+    }
+
+    cow_device = partition_name + "-cow";
     if (dm.GetDmDevicePathByName(cow_device, cow_path)) {
         return true;
     }
@@ -321,6 +336,12 @@ bool MapSnapshots::ApplyUpdate() {
 }
 
 bool MapSnapshots::BeginUpdate() {
+    if (metadata_super_ && !CreateScratchOtaMetadataOnSuper()) {
+        LOG(ERROR) << "Failed to create OTA metadata on super";
+        return false;
+    }
+    sm_ = SnapshotManager::New();
+
     lock_ = sm_->LockExclusive();
     std::vector<std::string> snapshots;
     sm_->ListSnapshots(lock_.get(), &snapshots);
@@ -470,10 +491,12 @@ bool MapSnapshots::FinishSnapshotWrites() {
 }
 
 bool MapSnapshots::UnmapCowImagePath(std::string& name) {
+    sm_ = SnapshotManager::New();
     return sm_->UnmapCowImage(name);
 }
 
 bool MapSnapshots::DeleteSnapshots() {
+    sm_ = SnapshotManager::New();
     lock_ = sm_->LockExclusive();
     if (!sm_->RemoveAllUpdateState(lock_.get())) {
         LOG(ERROR) << "Remove All Update State failed";
@@ -583,13 +606,19 @@ bool ApplyUpdate(int argc, char** argv) {
     }
 
     if (argc < 3) {
-        std::cerr << " apply-update <directory location where snapshot patches are present>"
+        std::cerr << " apply-update <directory location where snapshot patches are present> {-w}"
                      "    Apply the snapshots to the COW block device\n";
         return false;
     }
 
     std::string path = std::string(argv[2]);
-    MapSnapshots cow(path);
+    bool metadata_on_super = false;
+    if (argc == 4) {
+        if (std::string(argv[3]) == "-w") {
+            metadata_on_super = true;
+        }
+    }
+    MapSnapshots cow(path, metadata_on_super);
     if (!cow.ApplyUpdate()) {
         return false;
     }
@@ -607,7 +636,7 @@ bool MapPrecreatedSnapshots(int argc, char** argv) {
     }
 
     if (argc < 3) {
-        std::cerr << " map-snapshots <directory location where snapshot patches are present>"
+        std::cerr << " map-snapshots <directory location where snapshot patches are present> {-w}"
                      "    Map all snapshots based on patches present in the directory\n";
         return false;
     }
@@ -638,7 +667,14 @@ bool MapPrecreatedSnapshots(int argc, char** argv) {
         }
     }
 
-    MapSnapshots cow(path);
+    bool metadata_on_super = false;
+    if (argc == 4) {
+        if (std::string(argv[3]) == "-w") {
+            metadata_on_super = true;
+        }
+    }
+
+    MapSnapshots cow(path, metadata_on_super);
     if (!cow.BeginUpdate()) {
         LOG(ERROR) << "BeginUpdate failed";
         return false;

fs_mgr/libsnapshot/snapuserd/Android.bp

@@ -42,6 +42,7 @@ cc_library_static {
     static_libs: [
         "libcutils_sockets",
         "libfs_mgr_file_wait",
+        "libdm",
     ],
     shared_libs: [
         "libbase",
@@ -169,7 +170,7 @@ cc_binary {
     recovery_available: true,
 }
 
-// This target will install to /system/bin/snapuserd_ramdisk 
+// This target will install to /system/bin/snapuserd_ramdisk
 // It will also create a symblink on /system/bin/snapuserd that point to
 // /system/bin/snapuserd_ramdisk .
 // This way, init can check if generic ramdisk copy exists.
@@ -238,9 +239,19 @@ cc_defaults {
     test_options: {
         min_shipping_api_level: 30,
     },
+
+    compile_multilib: "both",
+    multilib: {
+        lib32: {
+            suffix: "32",
+        },
+        lib64: {
+            suffix: "64",
+        },
+    },
+
     auto_gen_config: true,
     require_root: true,
-    compile_multilib: "first",
 }
 
 cc_test {
@@ -248,8 +259,16 @@ cc_test {
     defaults: ["snapuserd_test_defaults"],
     host_supported: true,
     test_suites: [
-        "device-tests",
+        "general-tests",
     ],
+    test_options: {
+        test_runner_options: [
+            {
+                name: "force-no-test-error",
+                value: "false",
+            },
+        ],
+    },
 }
 
 // vts tests cannot be host_supported.
@@ -259,6 +278,10 @@ cc_test {
     test_suites: [
         "vts",
     ],
+    test_options: {
+        // VABC mandatory in Android T per VSR.
+        min_shipping_api_level: 32,
+    },
 }
 
 cc_binary_host {

fs_mgr/libsnapshot/snapuserd/dm_user_block_server.cpp

@@ -27,11 +27,12 @@ using android::base::unique_fd;
 DmUserBlockServer::DmUserBlockServer(const std::string& misc_name, unique_fd&& ctrl_fd,
                                      Delegate* delegate, size_t buffer_size)
     : misc_name_(misc_name), ctrl_fd_(std::move(ctrl_fd)), delegate_(delegate) {
-    buffer_.Initialize(buffer_size);
+    buffer_.Initialize(sizeof(struct dm_user_header), buffer_size);
 }
 
 bool DmUserBlockServer::ProcessRequests() {
-    struct dm_user_header* header = buffer_.GetHeaderPtr();
+    struct dm_user_header* header =
+            reinterpret_cast<struct dm_user_header*>(buffer_.GetHeaderPtr());
     if (!android::base::ReadFully(ctrl_fd_, header, sizeof(*header))) {
         if (errno != ENOTBLK) {
             SNAP_PLOG(ERROR) << "Control-read failed";
@@ -90,7 +91,8 @@ bool DmUserBlockServer::SendBufferedIo() {
 }
 
 void DmUserBlockServer::SendError() {
-    struct dm_user_header* header = buffer_.GetHeaderPtr();
+    struct dm_user_header* header =
+            reinterpret_cast<struct dm_user_header*>(buffer_.GetHeaderPtr());
     header->type = DM_USER_RESP_ERROR;
     // This is an issue with the dm-user interface. There
     // is no way to propagate the I/O error back to dm-user

fs_mgr/libsnapshot/snapuserd/include/snapuserd/dm_user_block_server.h

@@ -20,6 +20,7 @@
 
 #include <snapuserd/block_server.h>
 #include <snapuserd/snapuserd_buffer.h>
+#include <snapuserd/snapuserd_kernel.h>
 
 namespace android {
 namespace snapshot {

fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_buffer.h

@@ -27,13 +27,17 @@ namespace snapshot {
 
 class BufferSink final {
   public:
-    void Initialize(size_t size);
+    // Do not reserve any space of header by default
+    void Initialize(size_t size) { return Initialize(0, size); };
+    // This allows to set const header_size_ to be used if caller needs it
+    // for example, while working with dm_user
+    void Initialize(size_t header_size, size_t size);
     void* GetBufPtr() { return buffer_.get(); }
     void Clear() { memset(GetBufPtr(), 0, buffer_size_); }
     void* GetPayloadBuffer(size_t size);
     void* GetBuffer(size_t requested, size_t* actual);
     void UpdateBufferOffset(size_t size) { buffer_offset_ += size; }
-    struct dm_user_header* GetHeaderPtr();
+    void* GetHeaderPtr();
     void ResetBufferOffset() { buffer_offset_ = 0; }
     void* GetPayloadBufPtr();
     loff_t GetPayloadBytesWritten() { return buffer_offset_; }
@@ -56,6 +60,7 @@ class BufferSink final {
     std::unique_ptr<uint8_t[]> buffer_;
     loff_t buffer_offset_;
     size_t buffer_size_;
+    size_t header_size_;
 };
 
 }  // namespace snapshot

fs_mgr/libsnapshot/snapuserd/include/snapuserd/snapuserd_kernel.h

@@ -92,15 +92,5 @@ struct dm_user_header {
     __u64 len;
 } __attribute__((packed));
 
-struct dm_user_payload {
-    __u8 buf[];
-};
-
-// Message comprising both header and payload
-struct dm_user_message {
-    struct dm_user_header header;
-    struct dm_user_payload payload;
-};
-
 }  // namespace snapshot
 }  // namespace android

fs_mgr/libsnapshot/snapuserd/snapuserd_buffer.cpp

@@ -22,8 +22,9 @@
 namespace android {
 namespace snapshot {
 
-void BufferSink::Initialize(size_t size) {
+void BufferSink::Initialize(size_t header_size, size_t size) {
-    buffer_size_ = size + sizeof(struct dm_user_header);
+    header_size_ = header_size;
+    buffer_size_ = size + header_size;
     buffer_offset_ = 0;
     buffer_ = std::make_unique<uint8_t[]>(buffer_size_);
 }
@@ -41,11 +42,11 @@ void* BufferSink::AcquireBuffer(size_t size, size_t to_write) {
 
 void* BufferSink::GetPayloadBuffer(size_t size) {
     char* buffer = reinterpret_cast<char*>(GetBufPtr());
-    struct dm_user_message* msg = (struct dm_user_message*)(&(buffer[0]));
+
-    if ((buffer_size_ - buffer_offset_ - sizeof(msg->header)) < size) {
+    if ((buffer_size_ - buffer_offset_ - header_size_) < size) {
         return nullptr;
     }
-    return (char*)msg->payload.buf + buffer_offset_;
+    return (char*)(&buffer[0] + header_size_ + buffer_offset_);
 }
 
 void* BufferSink::GetBuffer(size_t requested, size_t* actual) {
@@ -58,19 +59,18 @@ void* BufferSink::GetBuffer(size_t requested, size_t* actual) {
     return buf;
 }
 
-struct dm_user_header* BufferSink::GetHeaderPtr() {
+void* BufferSink::GetHeaderPtr() {
-    if (!(sizeof(struct dm_user_header) <= buffer_size_)) {
+    // If no sufficient space or header not reserved
+    if (!(header_size_ <= buffer_size_) || !header_size_) {
         return nullptr;
     }
     char* buf = reinterpret_cast<char*>(GetBufPtr());
-    struct dm_user_header* header = (struct dm_user_header*)(&(buf[0]));
+    return (void*)(&(buf[0]));
-    return header;
 }
 
 void* BufferSink::GetPayloadBufPtr() {
     char* buffer = reinterpret_cast<char*>(GetBufPtr());
-    struct dm_user_message* msg = reinterpret_cast<struct dm_user_message*>(&(buffer[0]));
+    return &buffer[header_size_];
-    return msg->payload.buf;
 }
 
 }  // namespace snapshot

fs_mgr/libsnapshot/snapuserd/snapuserd_client.cpp

@@ -35,6 +35,7 @@
 #include <android-base/properties.h>
 #include <android-base/strings.h>
 #include <fs_mgr/file_wait.h>
+#include <libdm/dm.h>
 #include <snapuserd/snapuserd_client.h>
 
 namespace android {
@@ -333,7 +334,21 @@ bool SnapuserdClient::QueryUpdateVerification() {
 }
 
 std::string SnapuserdClient::GetDaemonAliveIndicatorPath() {
-    return "/metadata/ota/" + std::string(kDaemonAliveIndicator);
+    std::string metadata_dir;
+    std::string temp_metadata_mnt = "/mnt/scratch_ota_metadata_super";
+
+    auto& dm = ::android::dm::DeviceMapper::Instance();
+    auto partition_name = android::base::Basename(temp_metadata_mnt);
+
+    bool invalid_partition = (dm.GetState(partition_name) == dm::DmDeviceState::INVALID);
+    std::string temp_device;
+    if (!invalid_partition && dm.GetDmDevicePathByName(partition_name, &temp_device)) {
+        metadata_dir = temp_metadata_mnt + "/" + "ota/";
+    } else {
+        metadata_dir = "/metadata/ota/";
+    }
+
+    return metadata_dir + std::string(kDaemonAliveIndicator);
 }
 
 bool SnapuserdClient::IsTransitionedDaemonReady() {

fs_mgr/libsnapshot/snapuserd/snapuserd_daemon.cpp

@@ -30,6 +30,7 @@ DEFINE_bool(socket_handoff, false,
 DEFINE_bool(user_snapshot, false, "If true, user-space snapshots are used");
 DEFINE_bool(io_uring, false, "If true, io_uring feature is enabled");
 DEFINE_bool(o_direct, false, "If true, enable direct reads on source device");
+DEFINE_int32(cow_op_merge_size, 0, "number of operations to be processed at once");
 
 namespace android {
 namespace snapshot {
@@ -106,7 +107,6 @@ bool Daemon::StartServerForUserspaceSnapshots(int arg_start, int argc, char** ar
         }
         return user_server_.Run();
     }
-
     for (int i = arg_start; i < argc; i++) {
         auto parts = android::base::Split(argv[i], ",");
 
@@ -114,8 +114,8 @@ bool Daemon::StartServerForUserspaceSnapshots(int arg_start, int argc, char** ar
             LOG(ERROR) << "Malformed message, expected at least four sub-arguments.";
             return false;
         }
-        auto handler =
+        auto handler = user_server_.AddHandler(parts[0], parts[1], parts[2], parts[3],
-                user_server_.AddHandler(parts[0], parts[1], parts[2], parts[3], FLAGS_o_direct);
+                                               FLAGS_o_direct, FLAGS_cow_op_merge_size);
         if (!handler || !user_server_.StartHandler(parts[0])) {
             return false;
         }

fs_mgr/libsnapshot/snapuserd/user-space-merge/extractor.cpp

@@ -41,7 +41,7 @@ Extractor::Extractor(const std::string& base_path, const std::string& cow_path)
 bool Extractor::Init() {
     auto opener = factory_.CreateTestOpener(control_name_);
     handler_ = std::make_shared<SnapshotHandler>(control_name_, cow_path_, base_path_, base_path_,
-                                                 opener, 1, false, false, false);
+                                                 opener, 1, false, false, false, 0);
     if (!handler_->InitCowDevice()) {
         return false;
     }

fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.cpp

@@ -53,10 +53,10 @@ std::shared_ptr<HandlerThread> SnapshotHandlerManager::AddHandler(
         const std::string& misc_name, const std::string& cow_device_path,
         const std::string& backing_device, const std::string& base_path_merge,
         std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads, bool use_iouring,
-        bool o_direct) {
+        bool o_direct, uint32_t cow_op_merge_size) {
     auto snapuserd = std::make_shared<SnapshotHandler>(
             misc_name, cow_device_path, backing_device, base_path_merge, opener, num_worker_threads,
-            use_iouring, perform_verification_, o_direct);
+            use_iouring, perform_verification_, o_direct, cow_op_merge_size);
     if (!snapuserd->InitCowDevice()) {
         LOG(ERROR) << "Failed to initialize Snapuserd";
         return nullptr;

fs_mgr/libsnapshot/snapuserd/user-space-merge/handler_manager.h

@@ -52,13 +52,11 @@ class ISnapshotHandlerManager {
     virtual ~ISnapshotHandlerManager() {}
 
     // Add a new snapshot handler but do not start serving requests yet.
-    virtual std::shared_ptr<HandlerThread> AddHandler(const std::string& misc_name,
+    virtual std::shared_ptr<HandlerThread> AddHandler(
-                                                      const std::string& cow_device_path,
+            const std::string& misc_name, const std::string& cow_device_path,
-                                                      const std::string& backing_device,
+            const std::string& backing_device, const std::string& base_path_merge,
-                                                      const std::string& base_path_merge,
+            std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads, bool use_iouring,
-                                                      std::shared_ptr<IBlockServerOpener> opener,
+            bool o_direct, uint32_t cow_op_merge_size) = 0;
-                                                      int num_worker_threads, bool use_iouring,
-                                                      bool o_direct) = 0;
 
     // Start serving requests on a snapshot handler.
     virtual bool StartHandler(const std::string& misc_name) = 0;
@@ -98,7 +96,7 @@ class SnapshotHandlerManager final : public ISnapshotHandlerManager {
                                               const std::string& base_path_merge,
                                               std::shared_ptr<IBlockServerOpener> opener,
                                               int num_worker_threads, bool use_iouring,
-                                              bool o_direct) override;
+                                              bool o_direct, uint32_t cow_op_merge_size) override;
     bool StartHandler(const std::string& misc_name) override;
     bool DeleteHandler(const std::string& misc_name) override;
     bool InitiateMerge(const std::string& misc_name) override;

fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.cpp

@@ -17,6 +17,8 @@
 #include <libsnapshot/cow_format.h>
 #include <pthread.h>
 
+#include <android-base/properties.h>
+
 #include "merge_worker.h"
 #include "snapuserd_core.h"
 #include "utility.h"
@@ -30,12 +32,18 @@ using android::base::unique_fd;
 
 MergeWorker::MergeWorker(const std::string& cow_device, const std::string& misc_name,
                          const std::string& base_path_merge,
-                         std::shared_ptr<SnapshotHandler> snapuserd)
+                         std::shared_ptr<SnapshotHandler> snapuserd, uint32_t cow_op_merge_size)
-    : Worker(cow_device, misc_name, base_path_merge, snapuserd) {}
+    : Worker(cow_device, misc_name, base_path_merge, snapuserd),
+      cow_op_merge_size_(cow_op_merge_size) {}
 
 int MergeWorker::PrepareMerge(uint64_t* source_offset, int* pending_ops,
                               std::vector<const CowOperation*>* replace_zero_vec) {
     int num_ops = *pending_ops;
+    // 0 indicates ro.virtual_ab.cow_op_merge_size was not set in the build
+    if (cow_op_merge_size_ != 0) {
+        num_ops = std::min(cow_op_merge_size_, static_cast<uint32_t>(*pending_ops));
+    }
+
     int nr_consecutive = 0;
     bool checkOrderedOp = (replace_zero_vec == nullptr);
     size_t num_blocks = 1;
@@ -179,8 +187,8 @@ bool MergeWorker::MergeReplaceZeroOps() {
         bufsink_.ResetBufferOffset();
 
         if (snapuserd_->IsIOTerminated()) {
-            SNAP_LOG(ERROR)
+            SNAP_LOG(ERROR) << "MergeReplaceZeroOps: MergeWorker threads terminated - shutting "
-                    << "MergeReplaceZeroOps: MergeWorker threads terminated - shutting down merge";
+                               "down merge";
             return false;
         }
     }
@@ -577,8 +585,10 @@ bool MergeWorker::Run() {
         SNAP_LOG(ERROR) << "Merge terminated early...";
         return true;
     }
+    auto merge_thread_priority = android::base::GetUintProperty<uint32_t>(
+            "ro.virtual_ab.merge_thread_priority", ANDROID_PRIORITY_BACKGROUND);
 
-    if (!SetThreadPriority(ANDROID_PRIORITY_BACKGROUND)) {
+    if (!SetThreadPriority(merge_thread_priority)) {
         SNAP_PLOG(ERROR) << "Failed to set thread priority";
     }
 

fs_mgr/libsnapshot/snapuserd/user-space-merge/merge_worker.h

@@ -23,7 +23,8 @@ namespace snapshot {
 class MergeWorker : public Worker {
   public:
     MergeWorker(const std::string& cow_device, const std::string& misc_name,
-                const std::string& base_path_merge, std::shared_ptr<SnapshotHandler> snapuserd);
+                const std::string& base_path_merge, std::shared_ptr<SnapshotHandler> snapuserd,
+                uint32_t cow_op_merge_size);
     bool Run();
 
   private:
@@ -53,6 +54,7 @@ class MergeWorker : public Worker {
     // syscalls and fallback to synchronous I/O, we
     // don't want huge queue depth
     int queue_depth_ = 8;
+    uint32_t cow_op_merge_size_ = 0;
 };
 
 }  // namespace snapshot

fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.cpp

@@ -14,11 +14,14 @@
  * limitations under the License.
  */
 
+#include <android-base/properties.h>
+
 #include <libsnapshot/cow_format.h>
 #include <pthread.h>
 
 #include "read_worker.h"
 #include "snapuserd_core.h"
+#include "user-space-merge/worker.h"
 #include "utility.h"
 
 namespace android {
@@ -259,8 +262,10 @@ bool ReadWorker::Run() {
     SNAP_LOG(INFO) << "Processing snapshot I/O requests....";
 
     pthread_setname_np(pthread_self(), "ReadWorker");
+    auto worker_thread_priority = android::base::GetUintProperty<uint32_t>(
+            "ro.virtual_ab.worker_thread_priority", ANDROID_PRIORITY_NORMAL);
 
-    if (!SetThreadPriority(ANDROID_PRIORITY_NORMAL)) {
+    if (!SetThreadPriority(worker_thread_priority)) {
         SNAP_PLOG(ERROR) << "Failed to set thread priority";
     }
 

fs_mgr/libsnapshot/snapuserd/user-space-merge/read_worker.h

@@ -57,7 +57,7 @@ class ReadWorker : public Worker, public IBlockServer::Delegate {
     bool ReadFromSourceDevice(const CowOperation* cow_op, void* buffer);
     bool ReadDataFromBaseDevice(sector_t sector, void* buffer, size_t read_size);
 
-    constexpr bool IsBlockAligned(size_t size) { return ((size & (BLOCK_SZ - 1)) == 0); }
+    constexpr bool IsBlockAligned(uint64_t size) { return ((size & (BLOCK_SZ - 1)) == 0); }
     constexpr sector_t ChunkToSector(chunk_t chunk) { return chunk << CHUNK_SHIFT; }
     constexpr chunk_t SectorToChunk(sector_t sector) { return sector >> CHUNK_SHIFT; }
 

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.cpp

@@ -36,7 +36,8 @@ using android::base::unique_fd;
 SnapshotHandler::SnapshotHandler(std::string misc_name, std::string cow_device,
                                  std::string backing_device, std::string base_path_merge,
                                  std::shared_ptr<IBlockServerOpener> opener, int num_worker_threads,
-                                 bool use_iouring, bool perform_verification, bool o_direct) {
+                                 bool use_iouring, bool perform_verification, bool o_direct,
+                                 uint32_t cow_op_merge_size) {
     misc_name_ = std::move(misc_name);
     cow_device_ = std::move(cow_device);
     backing_store_device_ = std::move(backing_device);
@@ -46,6 +47,7 @@ SnapshotHandler::SnapshotHandler(std::string misc_name, std::string cow_device,
     is_io_uring_enabled_ = use_iouring;
     perform_verification_ = perform_verification;
     o_direct_ = o_direct;
+    cow_op_merge_size_ = cow_op_merge_size;
 }
 
 bool SnapshotHandler::InitializeWorkers() {
@@ -60,12 +62,11 @@ bool SnapshotHandler::InitializeWorkers() {
 
         worker_threads_.push_back(std::move(wt));
     }
-
     merge_thread_ = std::make_unique<MergeWorker>(cow_device_, misc_name_, base_path_merge_,
-                                                  GetSharedPtr());
+                                                  GetSharedPtr(), cow_op_merge_size_);
 
     read_ahead_thread_ = std::make_unique<ReadAhead>(cow_device_, backing_store_device_, misc_name_,
-                                                     GetSharedPtr());
+                                                     GetSharedPtr(), cow_op_merge_size_);
 
     update_verify_ = std::make_unique<UpdateVerify>(misc_name_);
 

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_core.h

@@ -104,7 +104,8 @@ class SnapshotHandler : public std::enable_shared_from_this<SnapshotHandler> {
   public:
     SnapshotHandler(std::string misc_name, std::string cow_device, std::string backing_device,
                     std::string base_path_merge, std::shared_ptr<IBlockServerOpener> opener,
-                    int num_workers, bool use_iouring, bool perform_verification, bool o_direct);
+                    int num_workers, bool use_iouring, bool perform_verification, bool o_direct,
+                    uint32_t cow_op_merge_size);
     bool InitCowDevice();
     bool Start();
 
@@ -247,7 +248,7 @@ class SnapshotHandler : public std::enable_shared_from_this<SnapshotHandler> {
     bool resume_merge_ = false;
     bool merge_complete_ = false;
     bool o_direct_ = false;
-
+    uint32_t cow_op_merge_size_ = 0;
     std::unique_ptr<UpdateVerify> update_verify_;
     std::shared_ptr<IBlockServerOpener> block_server_opener_;
 };

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.cpp

@@ -18,6 +18,7 @@
 
 #include <pthread.h>
 
+#include "android-base/properties.h"
 #include "snapuserd_core.h"
 #include "utility.h"
 
@@ -29,11 +30,13 @@ using namespace android::dm;
 using android::base::unique_fd;
 
 ReadAhead::ReadAhead(const std::string& cow_device, const std::string& backing_device,
-                     const std::string& misc_name, std::shared_ptr<SnapshotHandler> snapuserd) {
+                     const std::string& misc_name, std::shared_ptr<SnapshotHandler> snapuserd,
+                     uint32_t cow_op_merge_size) {
     cow_device_ = cow_device;
     backing_store_device_ = backing_device;
     misc_name_ = misc_name;
     snapuserd_ = snapuserd;
+    cow_op_merge_size_ = cow_op_merge_size;
 }
 
 void ReadAhead::CheckOverlap(const CowOperation* cow_op) {
@@ -62,8 +65,11 @@ int ReadAhead::PrepareNextReadAhead(uint64_t* source_offset, int* pending_ops,
                                     std::vector<uint64_t>& blocks,
                                     std::vector<const CowOperation*>& xor_op_vec) {
     int num_ops = *pending_ops;
-    int nr_consecutive = 0;
+    if (cow_op_merge_size_ != 0) {
+        num_ops = std::min(static_cast<int>(cow_op_merge_size_), *pending_ops);
+    }
 
+    int nr_consecutive = 0;
     bool is_ops_present = (!RAIterDone() && num_ops);
 
     if (!is_ops_present) {

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_readahead.h

@@ -35,7 +35,8 @@ class SnapshotHandler;
 class ReadAhead {
   public:
     ReadAhead(const std::string& cow_device, const std::string& backing_device,
-              const std::string& misc_name, std::shared_ptr<SnapshotHandler> snapuserd);
+              const std::string& misc_name, std::shared_ptr<SnapshotHandler> snapuserd,
+              uint32_t cow_op_merge_size);
     bool RunThread();
 
   private:
@@ -106,6 +107,7 @@ class ReadAhead {
     // syscalls and fallback to synchronous I/O, we
     // don't want huge queue depth
     int queue_depth_ = 8;
+    uint32_t cow_op_merge_size_;
     std::unique_ptr<struct io_uring> ring_;
 };
 

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.cpp

@@ -22,6 +22,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/socket.h>
+#include <sys/system_properties.h>
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -35,9 +36,6 @@
 #include <snapuserd/snapuserd_client.h>
 #include "snapuserd_server.h"
 
-#define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
-#include <sys/_system_properties.h>
-
 namespace android {
 namespace snapshot {
 
@@ -347,7 +345,8 @@ std::shared_ptr<HandlerThread> UserSnapshotServer::AddHandler(const std::string&
                                                               const std::string& cow_device_path,
                                                               const std::string& backing_device,
                                                               const std::string& base_path_merge,
-                                                              const bool o_direct) {
+                                                              const bool o_direct,
+                                                              uint32_t cow_op_merge_size) {
     // We will need multiple worker threads only during
     // device boot after OTA. For all other purposes,
     // one thread is sufficient. We don't want to consume
@@ -369,7 +368,8 @@ std::shared_ptr<HandlerThread> UserSnapshotServer::AddHandler(const std::string&
     auto opener = block_server_factory_->CreateOpener(misc_name);
 
     return handlers_->AddHandler(misc_name, cow_device_path, backing_device, base_path_merge,
-                                 opener, num_worker_threads, io_uring_enabled_, o_direct);
+                                 opener, num_worker_threads, io_uring_enabled_, o_direct,
+                                 cow_op_merge_size);
 }
 
 bool UserSnapshotServer::WaitForSocket() {

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_server.h

@@ -87,7 +87,8 @@ class UserSnapshotServer {
                                               const std::string& cow_device_path,
                                               const std::string& backing_device,
                                               const std::string& base_path_merge,
-                                              bool o_direct = false);
+                                              bool o_direct = false,
+                                              uint32_t cow_op_merge_size = 0);
     bool StartHandler(const std::string& misc_name);
 
     void SetTerminating() { terminating_ = true; }

fs_mgr/libsnapshot/snapuserd/user-space-merge/snapuserd_test.cpp

@@ -67,6 +67,7 @@ struct TestParam {
     std::string compression;
     int block_size;
     int num_threads;
+    uint32_t cow_op_merge_size;
 };
 
 class SnapuserdTestBase : public ::testing::TestWithParam<TestParam> {
@@ -79,6 +80,8 @@ class SnapuserdTestBase : public ::testing::TestWithParam<TestParam> {
     std::unique_ptr<ICowWriter> CreateCowDeviceInternal();
     std::unique_ptr<ICowWriter> CreateV3Cow();
 
+    unique_fd GetCowFd() { return unique_fd{dup(cow_system_->fd)}; }
+
     std::unique_ptr<ITestHarness> harness_;
     size_t size_ = 10_MiB;
     int total_base_size_ = 0;
@@ -101,7 +104,9 @@ void SnapuserdTestBase::SetUp() {
 #endif
 }
 
-void SnapuserdTestBase::TearDown() {}
+void SnapuserdTestBase::TearDown() {
+    cow_system_ = nullptr;
+}
 
 void SnapuserdTestBase::CreateBaseDevice() {
     total_base_size_ = (size_ * 5);
@@ -132,10 +137,7 @@ std::unique_ptr<ICowWriter> SnapuserdTestBase::CreateCowDeviceInternal() {
     CowOptions options;
     options.compression = "gz";
 
-    unique_fd fd(cow_system_->fd);
+    return CreateCowWriter(2, options, GetCowFd());
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(2, options, std::move(fd));
 }
 
 std::unique_ptr<ICowWriter> SnapuserdTestBase::CreateV3Cow() {
@@ -151,10 +153,7 @@ std::unique_ptr<ICowWriter> SnapuserdTestBase::CreateV3Cow() {
     std::string path = android::base::GetExecutableDirectory();
     cow_system_ = std::make_unique<TemporaryFile>(path);
 
-    unique_fd fd(cow_system_->fd);
+    return CreateCowWriter(3, options, GetCowFd());
-    cow_system_->fd = -1;
-
-    return CreateCowWriter(3, options, std::move(fd));
 }
 
 void SnapuserdTestBase::CreateCowDevice() {
@@ -710,9 +709,9 @@ void SnapuserdTest::InitCowDevice() {
     auto opener = factory->CreateOpener(system_device_ctrl_name_);
     handlers_->DisableVerification();
     const TestParam params = GetParam();
-    auto handler = handlers_->AddHandler(system_device_ctrl_name_, cow_system_->path,
+    auto handler = handlers_->AddHandler(
-                                         base_dev_->GetPath(), base_dev_->GetPath(), opener, 1,
+            system_device_ctrl_name_, cow_system_->path, base_dev_->GetPath(), base_dev_->GetPath(),
-                                         params.io_uring, params.o_direct);
+            opener, 1, params.io_uring, params.o_direct, params.cow_op_merge_size);
     ASSERT_NE(handler, nullptr);
     ASSERT_NE(handler->snapuserd(), nullptr);
 #ifdef __ANDROID__
@@ -1229,9 +1228,9 @@ void HandlerTest::InitializeDevice() {
     ASSERT_NE(opener_, nullptr);
 
     const TestParam params = GetParam();
-    handler_ = std::make_shared<SnapshotHandler>(system_device_ctrl_name_, cow_system_->path,
+    handler_ = std::make_shared<SnapshotHandler>(
-                                                 base_dev_->GetPath(), base_dev_->GetPath(),
+            system_device_ctrl_name_, cow_system_->path, base_dev_->GetPath(), base_dev_->GetPath(),
-                                                 opener_, 1, false, false, params.o_direct);
+            opener_, 1, false, false, params.o_direct, params.cow_op_merge_size);
     ASSERT_TRUE(handler_->InitCowDevice());
     ASSERT_TRUE(handler_->InitializeWorkers());
 
@@ -1509,6 +1508,7 @@ std::vector<TestParam> GetVariableBlockTestConfigs() {
                     param.num_threads = thread;
                     param.io_uring = io_uring;
                     param.o_direct = false;
+                    param.cow_op_merge_size = 0;
                     testParams.push_back(std::move(param));
                 }
             }
@@ -1530,6 +1530,14 @@ INSTANTIATE_TEST_SUITE_P(Io, HandlerTest, ::testing::ValuesIn(GetTestConfigs()))
 int main(int argc, char** argv) {
     ::testing::InitGoogleTest(&argc, argv);
 
+#ifdef __ANDROID__
+    if (!android::snapshot::CanUseUserspaceSnapshots() ||
+        android::snapshot::IsVendorFromAndroid12()) {
+        std::cerr << "snapuserd_test not supported on this device\n";
+        return 0;
+    }
+#endif
+
     gflags::ParseCommandLineFlags(&argc, &argv, false);
 
     return RUN_ALL_TESTS();

fs_mgr/libsnapshot/snapuserd/utility.cpp

@@ -14,11 +14,14 @@
 
 #include "utility.h"
 
+#include <android-base/properties.h>
 #include <sys/resource.h>
 #include <sys/utsname.h>
 #include <unistd.h>
 
 #include <android-base/file.h>
+#include <android-base/logging.h>
+#include <libdm/dm.h>
 #include <processgroup/processgroup.h>
 
 #include <private/android_filesystem_config.h>
@@ -27,6 +30,7 @@ namespace android {
 namespace snapshot {
 
 using android::base::unique_fd;
+using android::dm::DeviceMapper;
 
 bool SetThreadPriority([[maybe_unused]] int priority) {
 #ifdef __ANDROID__
@@ -61,5 +65,38 @@ bool KernelSupportsIoUring() {
     return major > 5 || (major == 5 && minor >= 6);
 }
 
+bool GetUserspaceSnapshotsEnabledProperty() {
+    return android::base::GetBoolProperty("ro.virtual_ab.userspace.snapshots.enabled", false);
+}
+
+bool KernelSupportsCompressedSnapshots() {
+    auto& dm = DeviceMapper::Instance();
+    return dm.GetTargetByName("user", nullptr);
+}
+
+bool IsVendorFromAndroid12() {
+    const std::string UNKNOWN = "unknown";
+    const std::string vendor_release =
+            android::base::GetProperty("ro.vendor.build.version.release_or_codename", UNKNOWN);
+
+    if (vendor_release.find("12") != std::string::npos) {
+        return true;
+    }
+    return false;
+}
+
+bool CanUseUserspaceSnapshots() {
+    if (!GetUserspaceSnapshotsEnabledProperty()) {
+        LOG(INFO) << "Virtual A/B - Userspace snapshots disabled";
+        return false;
+    }
+
+    if (!KernelSupportsCompressedSnapshots()) {
+        LOG(ERROR) << "Userspace snapshots requested, but no kernel support is available.";
+        return false;
+    }
+    return true;
+}
+
 }  // namespace snapshot
 }  // namespace android

fs_mgr/libsnapshot/snapuserd/utility.h

@@ -24,5 +24,10 @@ bool SetThreadPriority(int priority);
 bool SetProfiles(std::initializer_list<std::string_view> profiles);
 bool KernelSupportsIoUring();
 
+bool GetUserspaceSnapshotsEnabledProperty();
+bool KernelSupportsCompressedSnapshots();
+bool CanUseUserspaceSnapshots();
+bool IsVendorFromAndroid12();
+
 }  // namespace snapshot
 }  // namespace android

fs_mgr/tests/AndroidTest.xml

@@ -16,6 +16,7 @@
     <option name="config-descriptor:metadata" key="parameter" value="not_instant_app" />
     <option name="config-descriptor:metadata" key="parameter" value="multi_abi" />
     <option name="config-descriptor:metadata" key="parameter" value="secondary_user" />
+    <option name="config-descriptor:metadata" key="parameter" value="secondary_user_on_secondary_display" />
     <target_preparer class="com.android.compatibility.common.tradefed.targetprep.FilePusher">
         <option name="cleanup" value="true" />
         <option name="push" value="CtsFsMgrTestCases->/data/local/tmp/CtsFsMgrTestCases" />

fs_mgr/tests/fs_mgr_test.cpp

@@ -37,6 +37,10 @@
 using namespace android::fs_mgr;
 using namespace testing;
 
+#if !defined(MS_LAZYTIME)
+#define MS_LAZYTIME (1 << 25)
+#endif
+
 namespace {
 
 const std::string cmdline =
@@ -329,6 +333,7 @@ TEST(fs_mgr, fs_mgr_read_fstab_file_proc_mounts) {
                 {"private", MS_PRIVATE},
                 {"slave", MS_SLAVE},
                 {"shared", MS_SHARED},
+                {"lazytime", MS_LAZYTIME},
                 {"defaults", 0},
                 {0, 0},
         };
@@ -1062,23 +1067,6 @@ TEST(fs_mgr, DefaultFstabContainsUserdata) {
             << "Default fstab doesn't contain /data entry";
 }
 
-TEST(fs_mgr, UserdataMountedFromDefaultFstab) {
-    if (getuid() != 0) {
-        GTEST_SKIP() << "Must be run as root.";
-        return;
-    }
-    Fstab fstab;
-    ASSERT_TRUE(ReadDefaultFstab(&fstab)) << "Failed to read default fstab";
-    Fstab proc_mounts;
-    ASSERT_TRUE(ReadFstabFromFile("/proc/mounts", &proc_mounts)) << "Failed to read /proc/mounts";
-    auto mounted_entry = GetEntryForMountPoint(&proc_mounts, "/data");
-    ASSERT_NE(mounted_entry, nullptr) << "/data is not mounted";
-    std::string block_device;
-    ASSERT_TRUE(android::base::Realpath(mounted_entry->blk_device, &block_device));
-    ASSERT_NE(nullptr, fs_mgr_get_mounted_entry_for_userdata(&fstab, block_device))
-            << "/data wasn't mounted from default fstab";
-}
-
 TEST(fs_mgr, ReadFstabFromFile_FsMgrOptions_Readahead_Size_KB) {
     TemporaryFile tf;
     ASSERT_TRUE(tf.fd != -1);

healthd/healthd_mode_charger.cpp

@@ -306,8 +306,8 @@ void Charger::UpdateScreenState(int64_t now) {
 
     if (!batt_anim_.run || now < next_screen_transition_) return;
 
-    // If battery level is not ready, keep checking in the defined time
+    // If battery status is not ready, keep checking in the defined time
-    if (health_info_.battery_level == 0 && health_info_.battery_status == BatteryStatus::UNKNOWN) {
+    if (health_info_.battery_status == BatteryStatus::UNKNOWN) {
         if (wait_batt_level_timestamp_ == 0) {
             // Set max delay time and skip drawing screen
             wait_batt_level_timestamp_ = now + MAX_BATT_LEVEL_WAIT_TIME;
@@ -317,7 +317,7 @@ void Charger::UpdateScreenState(int64_t now) {
             // Do nothing, keep waiting
             return;
         }
-        // If timeout and battery level is still not ready, draw unknown battery
+        // If timeout and battery status is still not ready, draw unknown battery
     }
 
     if (healthd_draw_ == nullptr) return;

init/Android.bp

@@ -38,7 +38,6 @@ init_common_sources = [
     "capabilities.cpp",
     "epoll.cpp",
     "import_parser.cpp",
-    "interface_utils.cpp",
     "interprocess_fifo.cpp",
     "keychords.cpp",
     "parser.cpp",
@@ -85,10 +84,6 @@ init_device_sources = [
     "ueventd.cpp",
     "ueventd_parser.cpp",
 ]
-init_host_sources = [
-    "check_builtins.cpp",
-    "host_import_parser.cpp",
-]
 
 cc_library_static {
     name: "vendor_init",
@@ -170,7 +165,7 @@ libinit_cc_defaults {
         },
         release_write_appcompat_override_system_properties: {
             cflags: ["-DWRITE_APPCOMPAT_OVERRIDE_SYSTEM_PROPERTIES"],
-        }
+        },
     },
     static_libs: [
         "libavb",
@@ -198,7 +193,6 @@ libinit_cc_defaults {
         "libext4_utils",
         "libfs_mgr",
         "libgsi",
-        "libhidl-gen-utils",
         "libkeyutils",
         "liblog",
         "liblogwrap",
@@ -236,7 +230,6 @@ cc_defaults {
     ],
     whole_static_libs: [
         "libcap",
-        "libcom.android.sysprop.init",
     ],
     header_libs: ["bootimg_headers"],
     proto: {
@@ -340,7 +333,7 @@ cc_binary {
     static_libs: ["libinit.microdroid"],
     cflags: ["-DMICRODROID=1"],
     no_full_install: true,
-    visibility: ["//packages/modules/Virtualization/microdroid"],
+    visibility: ["//packages/modules/Virtualization/build/microdroid"],
 }
 
 soong_config_module_type {
@@ -348,7 +341,7 @@ soong_config_module_type {
     module_type: "cc_defaults",
     config_namespace: "ANDROID",
     bool_variables: ["BOARD_USES_RECOVERY_AS_BOOT"],
-    properties: ["installable"],
+    properties: ["no_full_install"],
 }
 
 // Do not install init_first_stage even with mma if we're system-as-root.
@@ -357,7 +350,7 @@ init_first_stage_cc_defaults {
     name: "init_first_stage_defaults",
     soong_config_variables: {
         BOARD_USES_RECOVERY_AS_BOOT: {
-            installable: false,
+            no_full_install: true,
         },
     },
 
@@ -618,8 +611,6 @@ cc_defaults {
     whole_static_libs: ["libcap"],
     shared_libs: [
         "libcutils",
-        "libhidl-gen-utils",
-        "libhidlmetadata",
         "liblog",
         "libprocessgroup",
         "libprotobuf-cpp-lite",
@@ -627,9 +618,6 @@ cc_defaults {
     proto: {
         type: "lite",
     },
-    generated_headers: [
-        "generated_stub_builtin_function_map",
-    ],
     target: {
         android: {
             enabled: false,
@@ -648,17 +636,43 @@ cc_defaults {
 cc_binary {
     name: "host_init_verifier",
     defaults: ["init_host_defaults"],
-    srcs: ["host_init_verifier.cpp"] + init_common_sources + init_host_sources,
+    srcs: [
+        "check_builtins.cpp",
+        "host_import_parser.cpp",
+        "host_init_verifier.cpp",
+        "interface_utils.cpp",
+    ] + init_common_sources,
     generated_headers: [
         "generated_android_ids",
+        "generated_stub_builtin_function_map",
     ],
+    shared_libs: [
+        "libhidl-gen-utils",
+        "libhidlmetadata",
+    ],
+}
+
+genrule {
+    name: "noop_builtin_function_map",
+    tool_files: ["host_builtin_map.py"],
+    out: ["noop_builtin_function_map.h"],
+    srcs: [
+        "builtins.cpp",
+        "noop_builtins.cpp",
+    ],
+    cmd: "$(location host_builtin_map.py) --builtins $(location builtins.cpp) --check_builtins $(location noop_builtins.cpp) > $(out)",
 }
 
 cc_library_host_static {
     name: "libinit_host",
     defaults: ["init_host_defaults"],
-    srcs: init_common_sources + init_host_sources,
+    srcs: [
+        "noop_builtins.cpp",
+    ] + init_common_sources,
     export_include_dirs: ["."],
+    generated_headers: [
+        "noop_builtin_function_map",
+    ],
     proto: {
         export_proto_headers: true,
     },
@@ -673,3 +687,11 @@ sh_binary {
     src: "extra_free_kbytes.sh",
     filename_from_src: true,
 }
+
+phony {
+    name: "init_vendor",
+    required: select(soong_config_variable("ANDROID", "BOARD_USES_RECOVERY_AS_BOOT"), {
+        true: [],
+        default: ["init_first_stage"],
+    }),
+}

init/Android.mk

@@ -1,16 +0,0 @@
-# Copyright 2005 The Android Open Source Project
-
-LOCAL_PATH:= $(call my-dir)
-
-include $(CLEAR_VARS)
-
-LOCAL_MODULE := init_vendor
-LOCAL_LICENSE_KINDS := SPDX-license-identifier-Apache-2.0
-LOCAL_LICENSE_CONDITIONS := notice
-LOCAL_NOTICE_FILE := $(LOCAL_PATH)/NOTICE
-ifneq ($(BOARD_USES_RECOVERY_AS_BOOT),true)
-LOCAL_REQUIRED_MODULES := \
-   init_first_stage \
-
-endif  # BOARD_USES_RECOVERY_AS_BOOT
-include $(BUILD_PHONY_PACKAGE)

init/README.md

@@ -499,9 +499,12 @@ have been omitted.
    4. `late-fs` - Mount partitions marked as latemounted.
    5. `post-fs-data` - Mount and configure `/data`; set up encryption. `/metadata` is
       reformatted here if it couldn't mount in first-stage init.
-   6. `zygote-start` - Start the zygote.
+   6. `post-fs-data-checkpointed` - Triggered when vold has completed committing a checkpoint
-   7. `early-boot` - After zygote has started.
+      after an OTA update. Not triggered if checkpointing is not needed or supported.
-   8. `boot` - After `early-boot` actions have completed.
+   7. `bpf-progs-loaded` - Starts things that want to start ASAP but need eBPF (incl. netd)
+   8. `zygote-start` - Start the zygote.
+   9. `early-boot` - After zygote has started.
+  10. `boot` - After `early-boot` actions have completed.
 
 Commands
 --------
@@ -634,7 +637,7 @@ provides the `aidl_lazy_test_1` interface.
   Properties are expanded within _level_.
 
 `mark_post_data`
-> Used to mark the point right after /data is mounted.
+> (This action is deprecated and no-op.)
 
 `mkdir <path> [<mode>] [<owner>] [<group>] [encryption=<action>] [key=<key>]`
 > Create a directory at _path_, optionally with the given mode, owner, and
@@ -743,6 +746,9 @@ provides the `aidl_lazy_test_1` interface.
   fstab.${ro.hardware} or fstab.${ro.hardware.platform} will be scanned for
   under /odm/etc, /vendor/etc, or / at runtime, in that order.
 
+`swapoff <path>`
+> Stops swapping to the file or block device specified by path.
+
 `symlink <target> <path>`
 > Create a symbolic link at _path_ with the value _target_
 
@@ -786,7 +792,6 @@ provides the `aidl_lazy_test_1` interface.
   If the file does not exist, it will be created. If it does exist,
   it will be truncated. Properties are expanded within _content_.
 
-
 Imports
 -------
 `import <path>`

init/block_dev_initializer.cpp

@@ -139,6 +139,10 @@ bool BlockDevInitializer::InitPlatformDevice(const std::string& dev_name) {
     return InitDevice("/sys/devices/platform", dev_name);
 }
 
+bool BlockDevInitializer::InitHvcDevice(const std::string& dev_name) {
+    return InitDevice("/sys/devices/virtual/tty", dev_name);
+}
+
 bool BlockDevInitializer::InitDevice(const std::string& syspath, const std::string& device_name) {
     bool found = false;
 

init/block_dev_initializer.h

@@ -34,6 +34,7 @@ class BlockDevInitializer final {
     bool InitDevices(std::set<std::string> devices);
     bool InitDmDevice(const std::string& device);
     bool InitPlatformDevice(const std::string& device);
+    bool InitHvcDevice(const std::string& device);
 
   private:
     ListenerAction HandleUevent(const Uevent& uevent, std::set<std::string>* devices);

init/builtins.cpp

@@ -36,6 +36,7 @@
 #include <sys/resource.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
+#include <sys/swap.h>
 #include <sys/syscall.h>
 #include <sys/system_properties.h>
 #include <sys/time.h>
@@ -46,7 +47,6 @@
 #include <map>
 #include <memory>
 
-#include <InitProperties.sysprop.h>
 #include <android-base/chrono_utils.h>
 #include <android-base/file.h>
 #include <android-base/logging.h>
@@ -609,8 +609,6 @@ static Result<void> queue_fs_event(int code) {
     return Error() << "Invalid code: " << code;
 }
 
-static int initial_mount_fstab_return_code = -1;
-
 /* <= Q: mount_all <fstab> [ <path> ]* [--<options>]*
  * >= R: mount_all [ <fstab> ] [--<options>]*
  *
@@ -651,19 +649,10 @@ static Result<void> do_mount_all(const BuiltinArguments& args) {
         import_late(mount_all->rc_paths);
     }
 
-    if (mount_fstab_result.userdata_mounted) {
-        // This call to fs_mgr_mount_all mounted userdata. Keep the result in
-        // order for userspace reboot to correctly remount userdata.
-        LOG(INFO) << "Userdata mounted using "
-                  << (mount_all->fstab_path.empty() ? "(default fstab)" : mount_all->fstab_path)
-                  << " result : " << mount_fstab_result.code;
-        initial_mount_fstab_return_code = mount_fstab_result.code;
-    }
-
     if (queue_event) {
         /* queue_fs_event will queue event based on mount_fstab return code
          * and return processed return code*/
-        auto queue_fs_result = queue_fs_event(mount_fstab_result.code);
+        auto queue_fs_result = queue_fs_event(mount_fstab_result);
         if (!queue_fs_result.ok()) {
             return Error() << "queue_fs_event() failed: " << queue_fs_result.error();
         }
@@ -1151,29 +1140,19 @@ static Result<void> ExecWithFunctionOnFailure(const std::vector<std::string>& ar
 }
 
 static Result<void> ExecVdcRebootOnFailure(const std::string& vdc_arg) {
-    bool should_reboot_into_recovery = true;
     auto reboot_reason = vdc_arg + "_failed";
-    if (android::sysprop::InitProperties::userspace_reboot_in_progress().value_or(false)) {
-        should_reboot_into_recovery = false;
-        reboot_reason = "userspace_failed," + vdc_arg;
-    }
 
-    auto reboot = [reboot_reason, should_reboot_into_recovery](const std::string& message) {
+    auto reboot = [reboot_reason](const std::string& message) {
         // TODO (b/122850122): support this in gsi
-        if (should_reboot_into_recovery) {
+        if (IsFbeEnabled() && !android::gsi::IsGsiRunning()) {
-            if (IsFbeEnabled() && !android::gsi::IsGsiRunning()) {
+            LOG(ERROR) << message << ": Rebooting into recovery, reason: " << reboot_reason;
-                LOG(ERROR) << message << ": Rebooting into recovery, reason: " << reboot_reason;
+            if (auto result = reboot_into_recovery(
-                if (auto result = reboot_into_recovery(
+                        {"--prompt_and_wipe_data", "--reason="s + reboot_reason});
-                            {"--prompt_and_wipe_data", "--reason="s + reboot_reason});
+                !result.ok()) {
-                    !result.ok()) {
+                LOG(FATAL) << "Could not reboot into recovery: " << result.error();
-                    LOG(FATAL) << "Could not reboot into recovery: " << result.error();
-                }
-            } else {
-                LOG(ERROR) << "Failure (reboot suppressed): " << reboot_reason;
             }
         } else {
-            LOG(ERROR) << message << ": rebooting, reason: " << reboot_reason;
+            LOG(ERROR) << "Failure (reboot suppressed): " << reboot_reason;
-            trigger_shutdown("reboot," + reboot_reason);
         }
     };
 
@@ -1181,29 +1160,6 @@ static Result<void> ExecVdcRebootOnFailure(const std::string& vdc_arg) {
     return ExecWithFunctionOnFailure(args, reboot);
 }
 
-static Result<void> do_remount_userdata(const BuiltinArguments& args) {
-    if (initial_mount_fstab_return_code == -1) {
-        return Error() << "Calling remount_userdata too early";
-    }
-    Fstab fstab;
-    if (!ReadDefaultFstab(&fstab)) {
-        // TODO(b/135984674): should we reboot here?
-        return Error() << "Failed to read fstab";
-    }
-    // TODO(b/135984674): check that fstab contains /data.
-    if (auto rc = fs_mgr_remount_userdata_into_checkpointing(&fstab); rc < 0) {
-        std::string proc_mounts_output;
-        android::base::ReadFileToString("/proc/mounts", &proc_mounts_output, true);
-        android::base::WriteStringToFile(proc_mounts_output,
-                                         "/metadata/userspacereboot/mount_info.txt");
-        trigger_shutdown("reboot,mount_userdata_failed");
-    }
-    if (auto result = queue_fs_event(initial_mount_fstab_return_code); !result.ok()) {
-        return Error() << "queue_fs_event() failed: " << result.error();
-    }
-    return {};
-}
-
 static Result<void> do_installkey(const BuiltinArguments& args) {
     if (!is_file_crypto()) return {};
 
@@ -1219,8 +1175,7 @@ static Result<void> do_init_user0(const BuiltinArguments& args) {
 }
 
 static Result<void> do_mark_post_data(const BuiltinArguments& args) {
-    ServiceList::GetInstance().MarkPostData();
+    LOG(INFO) << "deprecated action `mark_post_data` called.";
-
     return {};
 }
 
@@ -1319,6 +1274,13 @@ static Result<void> do_enter_default_mount_ns(const BuiltinArguments& args) {
     return {};
 }
 
+static Result<void> do_swapoff(const BuiltinArguments& args) {
+    if (!swapoff(args[1].c_str())) {
+        return ErrnoError() << "swapoff() failed";
+    }
+    return {};
+}
+
 // Builtin-function-map start
 const BuiltinFunctionMap& GetBuiltinFunctionMap() {
     constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max();
@@ -1364,7 +1326,6 @@ const BuiltinFunctionMap& GetBuiltinFunctionMap() {
         {"umount_all",              {0,     1,    {false,  do_umount_all}}},
         {"update_linker_config",    {0,     0,    {false,  do_update_linker_config}}},
         {"readahead",               {1,     2,    {true,   do_readahead}}},
-        {"remount_userdata",        {0,     0,    {false,  do_remount_userdata}}},
         {"restart",                 {1,     2,    {false,  do_restart}}},
         {"restorecon",              {1,     kMax, {true,   do_restorecon}}},
         {"restorecon_recursive",    {1,     kMax, {true,   do_restorecon_recursive}}},
@@ -1375,6 +1336,7 @@ const BuiltinFunctionMap& GetBuiltinFunctionMap() {
         {"start",                   {1,     1,    {false,  do_start}}},
         {"stop",                    {1,     1,    {false,  do_stop}}},
         {"swapon_all",              {0,     1,    {false,  do_swapon_all}}},
+        {"swapoff",                 {1,     1,    {false,  do_swapoff}}},
         {"enter_default_mount_ns",  {0,     0,    {false,  do_enter_default_mount_ns}}},
         {"symlink",                 {2,     2,    {true,   do_symlink}}},
         {"sysclktz",                {1,     1,    {false,  do_sysclktz}}},

init/devices.cpp

@@ -283,7 +283,7 @@ std::tuple<mode_t, uid_t, gid_t> DeviceHandler::GetDevicePermissions(
 
 void DeviceHandler::MakeDevice(const std::string& path, bool block, int major, int minor,
                                const std::vector<std::string>& links) const {
-    auto[mode, uid, gid] = GetDevicePermissions(path, links);
+    auto [mode, uid, gid] = GetDevicePermissions(path, links);
     mode |= (block ? S_IFBLK : S_IFCHR);
 
     std::string secontext;
@@ -330,11 +330,11 @@ void DeviceHandler::MakeDevice(const std::string& path, bool block, int major, i
             if (gid != s.st_gid) {
                 new_group = gid;
             }
-        if (mode != s.st_mode) {
+            if (mode != s.st_mode) {
-            if (chmod(path.c_str(), mode) != 0) {
+                if (chmod(path.c_str(), mode) != 0) {
-                PLOG(ERROR) << "Cannot chmod " << path << " to " << mode;
+                    PLOG(ERROR) << "Cannot chmod " << path << " to " << mode;
+                }
             }
-        }
         } else {
             PLOG(ERROR) << "Cannot stat " << path;
         }
@@ -532,7 +532,7 @@ void DeviceHandler::HandleAshmemUevent(const Uevent& uevent) {
         if (!ReadFileToString(boot_id_path, &boot_id)) {
             PLOG(ERROR) << "Cannot duplicate ashmem device node. Failed to read " << boot_id_path;
             return;
-        };
+        }
         boot_id = Trim(boot_id);
 
         Uevent dup_ashmem_uevent = uevent;
@@ -543,10 +543,10 @@ void DeviceHandler::HandleAshmemUevent(const Uevent& uevent) {
 }
 
 void DeviceHandler::HandleUevent(const Uevent& uevent) {
-  if (uevent.action == "add" || uevent.action == "change" ||
+    if (uevent.action == "add" || uevent.action == "change" || uevent.action == "bind" ||
-      uevent.action == "bind" || uevent.action == "online") {
+        uevent.action == "online") {
-    FixupSysPermissions(uevent.path, uevent.subsystem);
+        FixupSysPermissions(uevent.path, uevent.subsystem);
-  }
+    }
 
     // if it's not a /dev device, nothing to do
     if (uevent.major < 0 || uevent.minor < 0) return;

init/first_stage_init.cpp

@@ -38,6 +38,7 @@
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
 #include <android/avf_cc_flags.h>
+#include <fs_mgr.h>
 #include <modprobe/modprobe.h>
 #include <private/android_filesystem_config.h>
 
@@ -303,6 +304,22 @@ static BootMode GetBootMode(const std::string& cmdline, const std::string& bootc
     return BootMode::NORMAL_MODE;
 }
 
+static void MaybeResumeFromHibernation(const std::string& bootconfig) {
+    std::string hibernationResumeDevice;
+    android::fs_mgr::GetBootconfigFromString(bootconfig, "androidboot.hibernation_resume_device",
+                                             &hibernationResumeDevice);
+    if (!hibernationResumeDevice.empty()) {
+        android::base::unique_fd fd(open("/sys/power/resume", O_RDWR | O_CLOEXEC));
+        if (fd >= 0) {
+            if (!android::base::WriteStringToFd(hibernationResumeDevice, fd)) {
+                PLOG(ERROR) << "Failed to write to /sys/power/resume";
+            }
+        } else {
+            PLOG(ERROR) << "Failed to open /sys/power/resume";
+        }
+    }
+}
+
 static std::unique_ptr<FirstStageMount> CreateFirstStageMount(const std::string& cmdline) {
     auto ret = FirstStageMount::Create(cmdline);
     if (ret.ok()) {
@@ -442,6 +459,8 @@ int FirstStageMain(int argc, char** argv) {
                   << module_elapse_time.count() << " ms";
     }
 
+    MaybeResumeFromHibernation(bootconfig);
+
     std::unique_ptr<FirstStageMount> fsm;
 
     bool created_devices = false;

init/first_stage_mount.cpp

@@ -156,6 +156,13 @@ static Result<Fstab> ReadFirstStageFstabAndroid() {
     return fstab;
 }
 
+static bool IsRequestingMicrodroidVendorPartition(const std::string& cmdline) {
+    if (virtualization::IsEnableTpuAssignableDeviceFlagEnabled()) {
+        return access("/proc/device-tree/avf/vendor_hashtree_descriptor_root_digest", F_OK) == 0;
+    }
+    return cmdline.find("androidboot.microdroid.mount_vendor=1") != std::string::npos;
+}
+
 // Note: this is a temporary solution to avoid blocking devs that depend on /vendor partition in
 // Microdroid. For the proper solution the /vendor fstab should probably be defined in the DT.
 // TODO(b/285855430): refactor this
@@ -166,7 +173,7 @@ static Result<Fstab> ReadFirstStageFstabMicrodroid(const std::string& cmdline) {
     if (!ReadDefaultFstab(&fstab)) {
         return Error() << "failed to read fstab";
     }
-    if (cmdline.find("androidboot.microdroid.mount_vendor=1") == std::string::npos) {
+    if (!IsRequestingMicrodroidVendorPartition(cmdline)) {
         // We weren't asked to mount /vendor partition, filter it out from the fstab.
         auto predicate = [](const auto& entry) { return entry.mount_point == "/vendor"; };
         fstab.erase(std::remove_if(fstab.begin(), fstab.end(), predicate), fstab.end());
@@ -305,6 +312,11 @@ bool FirstStageMountVBootV2::InitDevices() {
             return false;
         }
     }
+
+    if (IsArcvm() && !block_dev_init_.InitHvcDevice("hvc1")) {
+        return false;
+    }
+
     return true;
 }
 
@@ -366,6 +378,14 @@ bool FirstStageMountVBootV2::CreateLogicalPartitions() {
     }
 
     if (SnapshotManager::IsSnapshotManagerNeeded()) {
+        auto init_devices = [this](const std::string& device) -> bool {
+            if (android::base::StartsWith(device, "/dev/block/dm-")) {
+                return block_dev_init_.InitDmDevice(device);
+            }
+            return block_dev_init_.InitDevices({device});
+        };
+
+        SnapshotManager::MapTempOtaMetadataPartitionIfNeeded(init_devices);
         auto sm = SnapshotManager::NewForFirstStageMount();
         if (!sm) {
             return false;

init/fuzzer/Android.bp

@@ -30,7 +30,6 @@ cc_defaults {
     shared_libs: [
         "libbase",
         "libfs_mgr",
-        "libhidl-gen-utils",
         "libkeyutils",
         "liblog",
         "libprocessgroup",
@@ -50,7 +49,6 @@ cc_fuzz {
     srcs: [
         "init_parser_fuzzer.cpp",
     ],
-    shared_libs: ["libhidlmetadata",],
     defaults: [
         "libinit_fuzzer_defaults",
     ],

init/fuzzer/init_parser_fuzzer.cpp

@@ -15,9 +15,7 @@
  */
 
 #include <fuzzer/FuzzedDataProvider.h>
-#include <hidl/metadata.h>
 #include <import_parser.h>
-#include <interface_utils.h>
 #include <rlimit_parser.h>
 
 using namespace android;
@@ -34,7 +32,6 @@ const std::string kValidPaths[] = {
 };
 
 const int32_t kMaxBytes = 256;
-const std::string kValidInterfaces = "android.frameworks.vr.composer@2.0::IVrComposerClient";
 
 class InitParserFuzzer {
   public:
@@ -44,9 +41,6 @@ class InitParserFuzzer {
   private:
     void InvokeParser();
     void InvokeLimitParser();
-    void InvokeInterfaceUtils();
-    InterfaceInheritanceHierarchyMap GenerateHierarchyMap();
-    std::vector<HidlInterfaceMetadata> GenerateInterfaceMetadata();
 
     FuzzedDataProvider fdp_;
 };
@@ -64,60 +58,6 @@ void InitParserFuzzer::InvokeLimitParser() {
     }
 }
 
-std::vector<HidlInterfaceMetadata> InitParserFuzzer::GenerateInterfaceMetadata() {
-    std::vector<HidlInterfaceMetadata> random_interface;
-    for (size_t idx = 0; idx < fdp_.ConsumeIntegral<size_t>(); ++idx) {
-        HidlInterfaceMetadata metadata;
-        metadata.name = fdp_.ConsumeRandomLengthString(kMaxBytes);
-        for (size_t idx1 = 0; idx1 < fdp_.ConsumeIntegral<size_t>(); ++idx1) {
-            metadata.inherited.push_back(fdp_.ConsumeRandomLengthString(kMaxBytes));
-        }
-        random_interface.push_back(metadata);
-    }
-    return random_interface;
-}
-
-InterfaceInheritanceHierarchyMap InitParserFuzzer::GenerateHierarchyMap() {
-    InterfaceInheritanceHierarchyMap result;
-    std::vector<HidlInterfaceMetadata> random_interface;
-    if (fdp_.ConsumeBool()) {
-        random_interface = GenerateInterfaceMetadata();
-    } else {
-        random_interface = HidlInterfaceMetadata::all();
-    }
-
-    for (const HidlInterfaceMetadata& iface : random_interface) {
-        std::set<FQName> inherited_interfaces;
-        for (const std::string& intf : iface.inherited) {
-            FQName fqname;
-            (void)fqname.setTo(intf);
-            inherited_interfaces.insert(fqname);
-        }
-        FQName fqname;
-        (void)fqname.setTo(iface.name);
-        result[fqname] = inherited_interfaces;
-    }
-    return result;
-}
-
-void InitParserFuzzer::InvokeInterfaceUtils() {
-    InterfaceInheritanceHierarchyMap hierarchy_map = GenerateHierarchyMap();
-    SetKnownInterfaces(hierarchy_map);
-    IsKnownInterface(fdp_.ConsumeRandomLengthString(kMaxBytes));
-    std::set<std::string> interface_set;
-    for (size_t idx = 0; idx < fdp_.ConsumeIntegral<size_t>(); ++idx) {
-        auto set_interface_values = fdp_.PickValueInArray<const std::function<void()>>({
-                [&]() {
-                    interface_set.insert(("aidl/" + fdp_.ConsumeRandomLengthString(kMaxBytes)));
-                },
-                [&]() { interface_set.insert(fdp_.ConsumeRandomLengthString(kMaxBytes)); },
-                [&]() { interface_set.insert(kValidInterfaces); },
-        });
-        set_interface_values();
-    }
-    CheckInterfaceInheritanceHierarchy(interface_set, hierarchy_map);
-}
-
 void InitParserFuzzer::InvokeParser() {
     Parser parser;
     std::string name = fdp_.ConsumeBool() ? fdp_.ConsumeRandomLengthString(kMaxBytes) : "import";
@@ -132,7 +72,6 @@ void InitParserFuzzer::Process() {
     while (fdp_.remaining_bytes()) {
         auto invoke_parser_fuzzer = fdp_.PickValueInArray<const std::function<void()>>({
                 [&]() { InvokeParser(); },
-                [&]() { InvokeInterfaceUtils(); },
                 [&]() { InvokeLimitParser(); },
         });
         invoke_parser_fuzzer();

init/host_init_verifier.cpp

@@ -297,9 +297,7 @@ int main(int argc, char** argv) {
     ActionManager& am = ActionManager::GetInstance();
     ServiceList& sl = ServiceList::GetInstance();
     Parser parser;
-    parser.AddSectionParser("service",
+    parser.AddSectionParser("service", std::make_unique<ServiceParser>(&sl, GetSubcontext()));
-                            std::make_unique<ServiceParser>(&sl, GetSubcontext(),
-                                                            *interface_inheritance_hierarchy_map));
     parser.AddSectionParser("on", std::make_unique<ActionParser>(&am, GetSubcontext()));
     parser.AddSectionParser("import", std::make_unique<HostImportParser>());
 
@@ -317,11 +315,23 @@ int main(int argc, char** argv) {
             return EXIT_FAILURE;
         }
     }
+
     size_t failures = parser.parse_error_count() + am.CheckAllCommands() + sl.CheckAllCommands();
     if (failures > 0) {
         LOG(ERROR) << "Failed to parse init scripts with " << failures << " error(s).";
         return EXIT_FAILURE;
     }
+
+    for (const auto& service : sl) {
+        if (const auto& result = CheckInterfaceInheritanceHierarchy(
+                    service->interfaces(), *interface_inheritance_hierarchy_map);
+            !result.ok()) {
+            LOG(ERROR) << service->filename() << ": invalid interface in service '"
+                       << service->name() << "': " << result.error();
+            return EXIT_FAILURE;
+        }
+    }
+
     return EXIT_SUCCESS;
 }