libbinder: RPC use 'status_t' over 'bool'

For ease of debugging/handling errors (I realized that binderRpcTest
currently crashes on Pixel 3 because of some missing kernel patches -
this would have been easier with this, and one potential (even if
temporary) solution would be to check the return code).

Bug: 167966510
Test: binderRpcTest, binderRpcBenchmark, binder_parcel_fuzzer,
    binder_rpc_fuzzer, binderHostDeviceTest
Change-Id: I1baa2e9380e0ec8f82f8ceb250f3eeb632dc5fbc

14 files changed, 157 insertions, 125 deletions

diff --git a/libs/binder/Binder.cpp b/libs/binder/Binder.cpp
index 628381cc19..d3eef4e88e 100644
--- a/libs/binder/Binder.cpp
+++ b/libs/binder/Binder.cpp
@@ -555,7 +555,9 @@ status_t BBinder::setRpcClientDebug(android::base::unique_fd socketFd,
         return status;
     }
     rpcServer->setRootObjectWeak(weakThis);
-    rpcServer->setupExternalServer(std::move(socketFd));
+    if (auto status = rpcServer->setupExternalServer(std::move(socketFd)); status != OK) {
+        return status;
+    }
     rpcServer->setMaxThreads(binderThreadPoolMaxCount);
     rpcServer->start();
     e->mRpcServerLinks.emplace(link);
diff --git a/libs/binder/RpcServer.cpp b/libs/binder/RpcServer.cpp
index 879e462e8f..4fa99c0e45 100644
--- a/libs/binder/RpcServer.cpp
+++ b/libs/binder/RpcServer.cpp
@@ -55,25 +55,25 @@ void RpcServer::iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction()
     mAgreedExperimental = true;
 }
 
-bool RpcServer::setupUnixDomainServer(const char* path) {
+status_t RpcServer::setupUnixDomainServer(const char* path) {
     return setupSocketServer(UnixSocketAddress(path));
 }
 
-bool RpcServer::setupVsockServer(unsigned int port) {
+status_t RpcServer::setupVsockServer(unsigned int port) {
     // realizing value w/ this type at compile time to avoid ubsan abort
     constexpr unsigned int kAnyCid = VMADDR_CID_ANY;
 
     return setupSocketServer(VsockSocketAddress(kAnyCid, port));
 }
 
-bool RpcServer::setupInetServer(const char* address, unsigned int port,
-                                unsigned int* assignedPort) {
+status_t RpcServer::setupInetServer(const char* address, unsigned int port,
+                                    unsigned int* assignedPort) {
     if (assignedPort != nullptr) *assignedPort = 0;
     auto aiStart = InetSocketAddress::getAddrInfo(address, port);
-    if (aiStart == nullptr) return false;
+    if (aiStart == nullptr) return UNKNOWN_ERROR;
     for (auto ai = aiStart.get(); ai != nullptr; ai = ai->ai_next) {
         InetSocketAddress socketAddress(ai->ai_addr, ai->ai_addrlen, address, port);
-        if (!setupSocketServer(socketAddress)) {
+        if (status_t status = setupSocketServer(socketAddress); status != OK) {
             continue;
         }
 
@@ -84,7 +84,7 @@ bool RpcServer::setupInetServer(const char* address, unsigned int port,
             int savedErrno = errno;
             ALOGE("Could not getsockname at %s: %s", socketAddress.toString().c_str(),
                   strerror(savedErrno));
-            return false;
+            return -savedErrno;
         }
         LOG_ALWAYS_FATAL_IF(len != sizeof(addr), "Wrong socket type: len %zu vs len %zu",
                             static_cast<size_t>(len), sizeof(addr));
@@ -97,11 +97,11 @@ bool RpcServer::setupInetServer(const char* address, unsigned int port,
             *assignedPort = realPort;
         }
 
-        return true;
+        return OK;
     }
     ALOGE("None of the socket address resolved for %s:%u can be set up as inet server.", address,
           port);
-    return false;
+    return UNKNOWN_ERROR;
 }
 
 void RpcServer::setMaxThreads(size_t threads) {
@@ -366,7 +366,7 @@ void RpcServer::establishConnection(sp<RpcServer>&& server, base::unique_fd clie
         }
 
         if (incoming) {
-            LOG_ALWAYS_FATAL_IF(!session->addOutgoingConnection(std::move(client), true),
+            LOG_ALWAYS_FATAL_IF(OK != session->addOutgoingConnection(std::move(client), true),
                                 "server state must already be initialized");
             return;
         }
@@ -383,21 +383,22 @@ void RpcServer::establishConnection(sp<RpcServer>&& server, base::unique_fd clie
     RpcSession::join(std::move(session), std::move(setupResult));
 }
 
-bool RpcServer::setupSocketServer(const RpcSocketAddress& addr) {
+status_t RpcServer::setupSocketServer(const RpcSocketAddress& addr) {
     LOG_RPC_DETAIL("Setting up socket server %s", addr.toString().c_str());
     LOG_ALWAYS_FATAL_IF(hasServer(), "Each RpcServer can only have one server.");
 
     unique_fd serverFd(
             TEMP_FAILURE_RETRY(socket(addr.addr()->sa_family, SOCK_STREAM | SOCK_CLOEXEC, 0)));
     if (serverFd == -1) {
-        ALOGE("Could not create socket: %s", strerror(errno));
-        return false;
+        int savedErrno = errno;
+        ALOGE("Could not create socket: %s", strerror(savedErrno));
+        return -savedErrno;
     }
 
     if (0 != TEMP_FAILURE_RETRY(bind(serverFd.get(), addr.addr(), addr.addrSize()))) {
         int savedErrno = errno;
         ALOGE("Could not bind socket at %s: %s", addr.toString().c_str(), strerror(savedErrno));
-        return false;
+        return -savedErrno;
     }
 
     // Right now, we create all threads at once, making accept4 slow. To avoid hanging the client,
@@ -407,16 +408,16 @@ bool RpcServer::setupSocketServer(const RpcSocketAddress& addr) {
     if (0 != TEMP_FAILURE_RETRY(listen(serverFd.get(), 50 /*backlog*/))) {
         int savedErrno = errno;
         ALOGE("Could not listen socket at %s: %s", addr.toString().c_str(), strerror(savedErrno));
-        return false;
+        return -savedErrno;
     }
 
     LOG_RPC_DETAIL("Successfully setup socket server %s", addr.toString().c_str());
 
-    if (!setupExternalServer(std::move(serverFd))) {
+    if (status_t status = setupExternalServer(std::move(serverFd)); status != OK) {
         ALOGE("Another thread has set up server while calling setupSocketServer. Race?");
-        return false;
+        return status;
     }
-    return true;
+    return OK;
 }
 
 void RpcServer::onSessionAllIncomingThreadsEnded(const sp<RpcSession>& session) {
@@ -449,15 +450,15 @@ unique_fd RpcServer::releaseServer() {
     return std::move(mServer);
 }
 
-bool RpcServer::setupExternalServer(base::unique_fd serverFd) {
+status_t RpcServer::setupExternalServer(base::unique_fd serverFd) {
     LOG_ALWAYS_FATAL_IF(!mAgreedExperimental, "no!");
     std::lock_guard<std::mutex> _l(mLock);
     if (mServer.ok()) {
         ALOGE("Each RpcServer can only have one server.");
-        return false;
+        return INVALID_OPERATION;
     }
     mServer = std::move(serverFd);
-    return true;
+    return OK;
 }
 
 } // namespace android
diff --git a/libs/binder/RpcSession.cpp b/libs/binder/RpcSession.cpp
index 7565f1b53c..11dc1ab862 100644
--- a/libs/binder/RpcSession.cpp
+++ b/libs/binder/RpcSession.cpp
@@ -107,54 +107,55 @@ std::optional<uint32_t> RpcSession::getProtocolVersion() {
     return mProtocolVersion;
 }
 
-bool RpcSession::setupUnixDomainClient(const char* path) {
+status_t RpcSession::setupUnixDomainClient(const char* path) {
     return setupSocketClient(UnixSocketAddress(path));
 }
 
-bool RpcSession::setupVsockClient(unsigned int cid, unsigned int port) {
+status_t RpcSession::setupVsockClient(unsigned int cid, unsigned int port) {
     return setupSocketClient(VsockSocketAddress(cid, port));
 }
 
-bool RpcSession::setupInetClient(const char* addr, unsigned int port) {
+status_t RpcSession::setupInetClient(const char* addr, unsigned int port) {
     auto aiStart = InetSocketAddress::getAddrInfo(addr, port);
-    if (aiStart == nullptr) return false;
+    if (aiStart == nullptr) return UNKNOWN_ERROR;
     for (auto ai = aiStart.get(); ai != nullptr; ai = ai->ai_next) {
         InetSocketAddress socketAddress(ai->ai_addr, ai->ai_addrlen, addr, port);
-        if (setupSocketClient(socketAddress)) return true;
+        if (status_t status = setupSocketClient(socketAddress); status == OK) return OK;
     }
     ALOGE("None of the socket address resolved for %s:%u can be added as inet client.", addr, port);
-    return false;
+    return NAME_NOT_FOUND;
 }
 
-bool RpcSession::setupPreconnectedClient(unique_fd fd, std::function<unique_fd()>&& request) {
-    return setupClient([&](const RpcAddress& sessionId, bool incoming) {
+status_t RpcSession::setupPreconnectedClient(unique_fd fd, std::function<unique_fd()>&& request) {
+    return setupClient([&](const RpcAddress& sessionId, bool incoming) -> status_t {
         // std::move'd from fd becomes -1 (!ok())
         if (!fd.ok()) {
             fd = request();
-            if (!fd.ok()) return false;
+            if (!fd.ok()) return BAD_VALUE;
         }
         return initAndAddConnection(std::move(fd), sessionId, incoming);
     });
 }
 
-bool RpcSession::addNullDebuggingClient() {
+status_t RpcSession::addNullDebuggingClient() {
     // Note: only works on raw sockets.
     unique_fd serverFd(TEMP_FAILURE_RETRY(open("/dev/null", O_WRONLY | O_CLOEXEC)));
 
     if (serverFd == -1) {
-        ALOGE("Could not connect to /dev/null: %s", strerror(errno));
-        return false;
+        int savedErrno = errno;
+        ALOGE("Could not connect to /dev/null: %s", strerror(savedErrno));
+        return -savedErrno;
     }
 
     auto ctx = mRpcTransportCtxFactory->newClientCtx();
     if (ctx == nullptr) {
         ALOGE("Unable to create RpcTransportCtx for null debugging client");
-        return false;
+        return NO_MEMORY;
     }
     auto server = ctx->newTransport(std::move(serverFd));
     if (server == nullptr) {
         ALOGE("Unable to set up RpcTransport");
-        return false;
+        return UNKNOWN_ERROR;
     }
     return addOutgoingConnection(std::move(server), false);
 }
@@ -475,8 +476,8 @@ sp<RpcServer> RpcSession::server() {
     return server;
 }
 
-bool RpcSession::setupClient(
-        const std::function<bool(const RpcAddress& sessionId, bool incoming)>& connectAndInit) {
+status_t RpcSession::setupClient(
+        const std::function<status_t(const RpcAddress& sessionId, bool incoming)>& connectAndInit) {
     {
         std::lock_guard<std::mutex> _l(mMutex);
         LOG_ALWAYS_FATAL_IF(mOutgoingConnections.size() != 0,
@@ -484,18 +485,23 @@ bool RpcSession::setupClient(
                             mOutgoingConnections.size());
     }
 
-    if (!connectAndInit(RpcAddress::zero(), false /*incoming*/)) return false;
+    if (status_t status = connectAndInit(RpcAddress::zero(), false /*incoming*/); status != OK)
+        return status;
 
     {
         ExclusiveConnection connection;
-        status_t status = ExclusiveConnection::find(sp<RpcSession>::fromExisting(this),
-                                                    ConnectionUse::CLIENT, &connection);
-        if (status != OK) return false;
+        if (status_t status = ExclusiveConnection::find(sp<RpcSession>::fromExisting(this),
+                                                        ConnectionUse::CLIENT, &connection);
+            status != OK)
+            return status;
 
         uint32_t version;
-        status = state()->readNewSessionResponse(connection.get(),
-                                                 sp<RpcSession>::fromExisting(this), &version);
-        if (!setProtocolVersion(version)) return false;
+        if (status_t status =
+                    state()->readNewSessionResponse(connection.get(),
+                                                    sp<RpcSession>::fromExisting(this), &version);
+            status != OK)
+            return status;
+        if (!setProtocolVersion(version)) return BAD_VALUE;
     }
 
     // TODO(b/189955605): we should add additional sessions dynamically
@@ -505,13 +511,13 @@ bool RpcSession::setupClient(
     if (status_t status = getRemoteMaxThreads(&numThreadsAvailable); status != OK) {
         ALOGE("Could not get max threads after initial session setup: %s",
               statusToString(status).c_str());
-        return false;
+        return status;
     }
 
     if (status_t status = readId(); status != OK) {
         ALOGE("Could not get session id after initial session setup: %s",
               statusToString(status).c_str());
-        return false;
+        return status;
     }
 
     // TODO(b/189955605): we should add additional sessions dynamically
@@ -522,24 +528,26 @@ bool RpcSession::setupClient(
 
     // we've already setup one client
     for (size_t i = 0; i + 1 < numThreadsAvailable; i++) {
-        if (!connectAndInit(mId.value(), false /*incoming*/)) return false;
+        if (status_t status = connectAndInit(mId.value(), false /*incoming*/); status != OK)
+            return status;
     }
 
     for (size_t i = 0; i < mMaxThreads; i++) {
-        if (!connectAndInit(mId.value(), true /*incoming*/)) return false;
+        if (status_t status = connectAndInit(mId.value(), true /*incoming*/); status != OK)
+            return status;
     }
 
-    return true;
+    return OK;
 }
 
-bool RpcSession::setupSocketClient(const RpcSocketAddress& addr) {
+status_t RpcSession::setupSocketClient(const RpcSocketAddress& addr) {
     return setupClient([&](const RpcAddress& sessionId, bool incoming) {
         return setupOneSocketConnection(addr, sessionId, incoming);
     });
 }
 
-bool RpcSession::setupOneSocketConnection(const RpcSocketAddress& addr, const RpcAddress& sessionId,
-                                          bool incoming) {
+status_t RpcSession::setupOneSocketConnection(const RpcSocketAddress& addr,
+                                              const RpcAddress& sessionId, bool incoming) {
     for (size_t tries = 0; tries < 5; tries++) {
         if (tries > 0) usleep(10000);
 
@@ -549,7 +557,7 @@ bool RpcSession::setupOneSocketConnection(const RpcSocketAddress& addr, const Rp
             int savedErrno = errno;
             ALOGE("Could not create socket at %s: %s", addr.toString().c_str(),
                   strerror(savedErrno));
-            return false;
+            return -savedErrno;
         }
 
         if (0 != TEMP_FAILURE_RETRY(connect(serverFd.get(), addr.addr(), addr.addrSize()))) {
@@ -560,7 +568,7 @@ bool RpcSession::setupOneSocketConnection(const RpcSocketAddress& addr, const Rp
             int savedErrno = errno;
             ALOGE("Could not connect socket at %s: %s", addr.toString().c_str(),
                   strerror(savedErrno));
-            return false;
+            return -savedErrno;
         }
         LOG_RPC_DETAIL("Socket at %s client with fd %d", addr.toString().c_str(), serverFd.get());
 
@@ -568,20 +576,21 @@ bool RpcSession::setupOneSocketConnection(const RpcSocketAddress& addr, const Rp
     }
 
     ALOGE("Ran out of retries to connect to %s", addr.toString().c_str());
-    return false;
+    return UNKNOWN_ERROR;
 }
 
-bool RpcSession::initAndAddConnection(unique_fd fd, const RpcAddress& sessionId, bool incoming) {
+status_t RpcSession::initAndAddConnection(unique_fd fd, const RpcAddress& sessionId,
+                                          bool incoming) {
     auto ctx = mRpcTransportCtxFactory->newClientCtx();
     if (ctx == nullptr) {
         ALOGE("Unable to create client RpcTransportCtx with %s sockets",
               mRpcTransportCtxFactory->toCString());
-        return false;
+        return NO_MEMORY;
     }
     auto server = ctx->newTransport(std::move(fd));
     if (server == nullptr) {
         ALOGE("Unable to set up RpcTransport in %s context", mRpcTransportCtxFactory->toCString());
-        return false;
+        return UNKNOWN_ERROR;
     }
 
     LOG_RPC_DETAIL("Socket at client with RpcTransport %p", server.get());
@@ -598,12 +607,12 @@ bool RpcSession::initAndAddConnection(unique_fd fd, const RpcAddress& sessionId,
     if (!sentHeader.ok()) {
         ALOGE("Could not write connection header to socket: %s",
               sentHeader.error().message().c_str());
-        return false;
+        return -sentHeader.error().code();
     }
     if (*sentHeader != sizeof(header)) {
         ALOGE("Could not write connection header to socket: sent %zd bytes, expected %zd",
               *sentHeader, sizeof(header));
-        return false;
+        return UNKNOWN_ERROR;
     }
 
     LOG_RPC_DETAIL("Socket at client: header sent");
@@ -615,7 +624,7 @@ bool RpcSession::initAndAddConnection(unique_fd fd, const RpcAddress& sessionId,
     }
 }
 
-bool RpcSession::addIncomingConnection(std::unique_ptr<RpcTransport> rpcTransport) {
+status_t RpcSession::addIncomingConnection(std::unique_ptr<RpcTransport> rpcTransport) {
     std::mutex mutex;
     std::condition_variable joinCv;
     std::unique_lock<std::mutex> lock(mutex);
@@ -641,10 +650,10 @@ bool RpcSession::addIncomingConnection(std::unique_ptr<RpcTransport> rpcTranspor
     });
     joinCv.wait(lock, [&] { return ownershipTransferred; });
     LOG_ALWAYS_FATAL_IF(!ownershipTransferred);
-    return true;
+    return OK;
 }
 
-bool RpcSession::addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTransport, bool init) {
+status_t RpcSession::addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTransport, bool init) {
     sp<RpcConnection> connection = sp<RpcConnection>::make();
     {
         std::lock_guard<std::mutex> _l(mMutex);
@@ -654,7 +663,7 @@ bool RpcSession::addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTranspor
         if (mShutdownTrigger == nullptr) {
             mShutdownTrigger = FdTrigger::make();
             mEventListener = mShutdownListener = sp<WaitForShutdownListener>::make();
-            if (mShutdownTrigger == nullptr) return false;
+            if (mShutdownTrigger == nullptr) return INVALID_OPERATION;
         }
 
         connection->rpcTransport = std::move(rpcTransport);
@@ -672,7 +681,7 @@ bool RpcSession::addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTranspor
         connection->exclusiveTid = std::nullopt;
     }
 
-    return status == OK;
+    return status;
 }
 
 bool RpcSession::setForServer(const wp<RpcServer>& server, const wp<EventListener>& eventListener,
diff --git a/libs/binder/ServiceManagerHost.cpp b/libs/binder/ServiceManagerHost.cpp
index 1c2f9b4314..59334b7542 100644
--- a/libs/binder/ServiceManagerHost.cpp
+++ b/libs/binder/ServiceManagerHost.cpp
@@ -158,8 +158,10 @@ sp<IBinder> getDeviceService(std::vector<std::string>&& serviceDispatcherArgs) {
     LOG_ALWAYS_FATAL_IF(!forwardResult->hostPort().has_value());
 
     auto rpcSession = RpcSession::make();
-    if (!rpcSession->setupInetClient("127.0.0.1", *forwardResult->hostPort())) {
-        ALOGE("Unable to set up inet client on host port %u", *forwardResult->hostPort());
+    if (status_t status = rpcSession->setupInetClient("127.0.0.1", *forwardResult->hostPort());
+        status != OK) {
+        ALOGE("Unable to set up inet client on host port %u: %s", *forwardResult->hostPort(),
+              statusToString(status).c_str());
         return nullptr;
     }
     auto binder = rpcSession->getRootObject();
diff --git a/libs/binder/include/binder/RpcServer.h b/libs/binder/include/binder/RpcServer.h
index 4abf3b914c..f79d85f5af 100644
--- a/libs/binder/include/binder/RpcServer.h
+++ b/libs/binder/include/binder/RpcServer.h
@@ -59,12 +59,12 @@ public:
      *     process B makes binder b and sends it to A
      *     A uses this 'back session' to send things back to B
      */
-    [[nodiscard]] bool setupUnixDomainServer(const char* path);
+    [[nodiscard]] status_t setupUnixDomainServer(const char* path);
 
     /**
      * Creates an RPC server at the current port.
      */
-    [[nodiscard]] bool setupVsockServer(unsigned int port);
+    [[nodiscard]] status_t setupVsockServer(unsigned int port);
 
     /**
      * Creates an RPC server at the current port using IPv4.
@@ -80,8 +80,8 @@ public:
      * "0.0.0.0" allows for connections on any IP address that the device may
      * have
      */
-    [[nodiscard]] bool setupInetServer(const char* address, unsigned int port,
-                                       unsigned int* assignedPort);
+    [[nodiscard]] status_t setupInetServer(const char* address, unsigned int port,
+                                           unsigned int* assignedPort);
 
     /**
      * If setup*Server has been successful, return true. Otherwise return false.
@@ -97,7 +97,7 @@ public:
      * Set up server using an external FD previously set up by releaseServer().
      * Return false if there's already a server.
      */
-    bool setupExternalServer(base::unique_fd serverFd);
+    [[nodiscard]] status_t setupExternalServer(base::unique_fd serverFd);
 
     void iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
 
@@ -175,7 +175,7 @@ private:
     void onSessionIncomingThreadEnded() override;
 
     static void establishConnection(sp<RpcServer>&& server, base::unique_fd clientFd);
-    bool setupSocketServer(const RpcSocketAddress& address);
+    status_t setupSocketServer(const RpcSocketAddress& address);
 
     const std::unique_ptr<RpcTransportCtxFactory> mRpcTransportCtxFactory;
     bool mAgreedExperimental = false;
diff --git a/libs/binder/include/binder/RpcSession.h b/libs/binder/include/binder/RpcSession.h
index 0b46606d63..7ed6e4373e 100644
--- a/libs/binder/include/binder/RpcSession.h
+++ b/libs/binder/include/binder/RpcSession.h
@@ -78,17 +78,17 @@ public:
      * This should be called once per thread, matching 'join' in the remote
      * process.
      */
-    [[nodiscard]] bool setupUnixDomainClient(const char* path);
+    [[nodiscard]] status_t setupUnixDomainClient(const char* path);
 
     /**
      * Connects to an RPC server at the CVD & port.
      */
-    [[nodiscard]] bool setupVsockClient(unsigned int cvd, unsigned int port);
+    [[nodiscard]] status_t setupVsockClient(unsigned int cvd, unsigned int port);
 
     /**
      * Connects to an RPC server at the given address and port.
      */
-    [[nodiscard]] bool setupInetClient(const char* addr, unsigned int port);
+    [[nodiscard]] status_t setupInetClient(const char* addr, unsigned int port);
 
     /**
      * Starts talking to an RPC server which has already been connected to. This
@@ -100,8 +100,8 @@ public:
      *
      * For future compatibility, 'request' should not reference any stack data.
      */
-    [[nodiscard]] bool setupPreconnectedClient(base::unique_fd fd,
-                                               std::function<base::unique_fd()>&& request);
+    [[nodiscard]] status_t setupPreconnectedClient(base::unique_fd fd,
+                                                   std::function<base::unique_fd()>&& request);
 
     /**
      * For debugging!
@@ -110,7 +110,7 @@ public:
      * response will never be satisfied. All data sent here will be
      * unceremoniously cast down the bottomless pit, /dev/null.
      */
-    [[nodiscard]] bool addNullDebuggingClient();
+    [[nodiscard]] status_t addNullDebuggingClient();
 
     /**
      * Query the other side of the session for the root object hosted by that
@@ -253,15 +253,17 @@ private:
     // join on thread passed to preJoinThreadOwnership
     static void join(sp<RpcSession>&& session, PreJoinSetupResult&& result);
 
-    [[nodiscard]] bool setupClient(
-            const std::function<bool(const RpcAddress& sessionId, bool incoming)>& connectAndInit);
-    [[nodiscard]] bool setupSocketClient(const RpcSocketAddress& address);
-    [[nodiscard]] bool setupOneSocketConnection(const RpcSocketAddress& address,
-                                                const RpcAddress& sessionId, bool incoming);
-    [[nodiscard]] bool initAndAddConnection(base::unique_fd fd, const RpcAddress& sessionId,
-                                            bool incoming);
-    [[nodiscard]] bool addIncomingConnection(std::unique_ptr<RpcTransport> rpcTransport);
-    [[nodiscard]] bool addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTransport, bool init);
+    [[nodiscard]] status_t setupClient(
+            const std::function<status_t(const RpcAddress& sessionId, bool incoming)>&
+                    connectAndInit);
+    [[nodiscard]] status_t setupSocketClient(const RpcSocketAddress& address);
+    [[nodiscard]] status_t setupOneSocketConnection(const RpcSocketAddress& address,
+                                                    const RpcAddress& sessionId, bool incoming);
+    [[nodiscard]] status_t initAndAddConnection(base::unique_fd fd, const RpcAddress& sessionId,
+                                                bool incoming);
+    [[nodiscard]] status_t addIncomingConnection(std::unique_ptr<RpcTransport> rpcTransport);
+    [[nodiscard]] status_t addOutgoingConnection(std::unique_ptr<RpcTransport> rpcTransport,
+                                                 bool init);
     [[nodiscard]] bool setForServer(const wp<RpcServer>& server,
                                     const wp<RpcSession::EventListener>& eventListener,
                                     const RpcAddress& sessionId);
diff --git a/libs/binder/libbinder_rpc_unstable.cpp b/libs/binder/libbinder_rpc_unstable.cpp
index 68ec669c31..bcb13aebdd 100644
--- a/libs/binder/libbinder_rpc_unstable.cpp
+++ b/libs/binder/libbinder_rpc_unstable.cpp
@@ -19,16 +19,20 @@
 #include <binder/RpcServer.h>
 #include <binder/RpcSession.h>
 
+using android::OK;
 using android::RpcServer;
 using android::RpcSession;
+using android::status_t;
+using android::statusToString;
 
 extern "C" {
 
 bool RunRpcServer(AIBinder* service, unsigned int port) {
     auto server = RpcServer::make();
     server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
-    if (!server->setupVsockServer(port)) {
-        LOG(ERROR) << "Failed to set up vsock server with port " << port;
+    if (status_t status = server->setupVsockServer(port); status != OK) {
+        LOG(ERROR) << "Failed to set up vsock server with port " << port
+                   << " error: " << statusToString(status).c_str();
         return false;
     }
     server->setRootObject(AIBinder_toPlatformBinder(service));
@@ -41,8 +45,9 @@ bool RunRpcServer(AIBinder* service, unsigned int port) {
 
 AIBinder* RpcClient(unsigned int cid, unsigned int port) {
     auto session = RpcSession::make();
-    if (!session->setupVsockClient(cid, port)) {
-        LOG(ERROR) << "Failed to set up vsock client with CID " << cid << " and port " << port;
+    if (status_t status = session->setupVsockClient(cid, port); status != OK) {
+        LOG(ERROR) << "Failed to set up vsock client with CID " << cid << " and port " << port
+                   << " error: " << statusToString(status).c_str();
         return nullptr;
     }
     return AIBinder_fromPlatformBinder(session->getRootObject());
diff --git a/libs/binder/servicedispatcher.cpp b/libs/binder/servicedispatcher.cpp
index a6e3f7d1f5..48fc60ac77 100644
--- a/libs/binder/servicedispatcher.cpp
+++ b/libs/binder/servicedispatcher.cpp
@@ -33,6 +33,7 @@ using android::defaultServiceManager;
 using android::OK;
 using android::RpcServer;
 using android::sp;
+using android::status_t;
 using android::statusToString;
 using android::String16;
 using android::base::Basename;
@@ -87,8 +88,8 @@ int Dispatch(const char* name, const ServiceRetriever& serviceRetriever) {
     }
     rpcServer->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
     unsigned int port;
-    if (!rpcServer->setupInetServer(kLocalInetAddress, 0, &port)) {
-        LOG(ERROR) << "setupInetServer failed";
+    if (status_t status = rpcServer->setupInetServer(kLocalInetAddress, 0, &port); status != OK) {
+        LOG(ERROR) << "setupInetServer failed: " << statusToString(status);
         return EX_SOFTWARE;
     }
     auto socket = rpcServer->releaseServer();
@@ -200,8 +201,8 @@ int wrapServiceManager(const ServiceRetriever& serviceRetriever) {
     rpcServer->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
     rpcServer->setRootObject(service);
     unsigned int port;
-    if (!rpcServer->setupInetServer(kLocalInetAddress, 0, &port)) {
-        LOG(ERROR) << "Unable to set up inet server";
+    if (status_t status = rpcServer->setupInetServer(kLocalInetAddress, 0, &port); status != OK) {
+        LOG(ERROR) << "Unable to set up inet server: " << statusToString(status);
         return EX_SOFTWARE;
     }
     LOG(INFO) << "Finish wrapping servicemanager with RPC on port " << port;
diff --git a/libs/binder/tests/binderHostDeviceTest.cpp b/libs/binder/tests/binderHostDeviceTest.cpp
index 5dd92121ba..3f72b8f58a 100644
--- a/libs/binder/tests/binderHostDeviceTest.cpp
+++ b/libs/binder/tests/binderHostDeviceTest.cpp
@@ -101,8 +101,9 @@ public:
 
     [[nodiscard]] static sp<IBinder> get(unsigned int hostPort) {
         auto rpcSession = RpcSession::make();
-        if (!rpcSession->setupInetClient("127.0.0.1", hostPort)) {
-            ADD_FAILURE() << "Failed to setupInetClient on " << hostPort;
+        if (status_t status = rpcSession->setupInetClient("127.0.0.1", hostPort); status != OK) {
+            ADD_FAILURE() << "Failed to setupInetClient on " << hostPort << ": "
+                          << statusToString(status);
             return nullptr;
         }
         return rpcSession->getRootObject();
diff --git a/libs/binder/tests/binderLibTest.cpp b/libs/binder/tests/binderLibTest.cpp
index 65db7f65cf..eea7d8c108 100644
--- a/libs/binder/tests/binderLibTest.cpp
+++ b/libs/binder/tests/binderLibTest.cpp
@@ -1192,8 +1192,8 @@ public:
         if (rpcServer == nullptr) return {};
         rpcServer->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
         unsigned int port;
-        if (!rpcServer->setupInetServer("127.0.0.1", 0, &port)) {
-            ADD_FAILURE() << "setupInetServer failed";
+        if (status_t status = rpcServer->setupInetServer("127.0.0.1", 0, &port); status != OK) {
+            ADD_FAILURE() << "setupInetServer failed" << statusToString(status);
             return {};
         }
         return {rpcServer->releaseServer(), port};
diff --git a/libs/binder/tests/binderRpcBenchmark.cpp b/libs/binder/tests/binderRpcBenchmark.cpp
index 5f4a7b5592..8d75a531ec 100644
--- a/libs/binder/tests/binderRpcBenchmark.cpp
+++ b/libs/binder/tests/binderRpcBenchmark.cpp
@@ -42,6 +42,8 @@ using android::ProcessState;
 using android::RpcServer;
 using android::RpcSession;
 using android::sp;
+using android::status_t;
+using android::statusToString;
 using android::String16;
 using android::binder::Status;
 
@@ -160,7 +162,7 @@ int main(int argc, char** argv) {
         sp<RpcServer> server = RpcServer::make();
         server->setRootObject(sp<MyBinderRpcBenchmark>::make());
         server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
-        CHECK(server->setupUnixDomainServer(addr.c_str()));
+        CHECK_EQ(OK, server->setupUnixDomainServer(addr.c_str()));
         server->join();
         exit(1);
     }
@@ -182,11 +184,13 @@ int main(int argc, char** argv) {
     CHECK_NE(nullptr, gKernelBinder.get());
 #endif
 
+    status_t status;
     for (size_t tries = 0; tries < 5; tries++) {
         usleep(10000);
-        if (gSession->setupUnixDomainClient(addr.c_str())) goto success;
+        status = gSession->setupUnixDomainClient(addr.c_str());
+        if (status == OK) goto success;
     }
-    LOG(FATAL) << "Could not connect.";
+    LOG(FATAL) << "Could not connect: " << statusToString(status).c_str();
 success:
 
     ::benchmark::RunSpecifiedBenchmarks();
diff --git a/libs/binder/tests/binderRpcTest.cpp b/libs/binder/tests/binderRpcTest.cpp
index 36a6804bcd..6dd4019ae8 100644
--- a/libs/binder/tests/binderRpcTest.cpp
+++ b/libs/binder/tests/binderRpcTest.cpp
@@ -89,7 +89,7 @@ TEST_P(BinderRpcSimple, SetExternalServerTest) {
     auto server = RpcServer::make(newFactory(GetParam()));
     server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
     ASSERT_FALSE(server->hasServer());
-    ASSERT_TRUE(server->setupExternalServer(std::move(sink)));
+    ASSERT_EQ(OK, server->setupExternalServer(std::move(sink)));
     ASSERT_TRUE(server->hasServer());
     base::unique_fd retrieved = server->releaseServer();
     ASSERT_FALSE(server->hasServer());
@@ -484,13 +484,13 @@ public:
                         case SocketType::PRECONNECTED:
                             [[fallthrough]];
                         case SocketType::UNIX:
-                            CHECK(server->setupUnixDomainServer(addr.c_str())) << addr;
+                            CHECK_EQ(OK, server->setupUnixDomainServer(addr.c_str())) << addr;
                             break;
                         case SocketType::VSOCK:
-                            CHECK(server->setupVsockServer(vsockPort));
+                            CHECK_EQ(OK, server->setupVsockServer(vsockPort));
                             break;
                         case SocketType::INET: {
-                            CHECK(server->setupInetServer(kLocalInetAddress, 0, &outPort));
+                            CHECK_EQ(OK, server->setupInetServer(kLocalInetAddress, 0, &outPort));
                             CHECK_NE(0, outPort);
                             break;
                         }
@@ -516,30 +516,35 @@ public:
             CHECK_NE(0, outPort);
         }
 
+        status_t status;
+
         for (size_t i = 0; i < options.numSessions; i++) {
             sp<RpcSession> session = RpcSession::make(newFactory(rpcSecurity));
             session->setMaxThreads(options.numIncomingConnections);
 
             switch (socketType) {
                 case SocketType::PRECONNECTED:
-                    if (session->setupPreconnectedClient({}, [=]() {
-                            return connectToUds(addr.c_str());
-                        }))
-                        goto success;
+                    status = session->setupPreconnectedClient({}, [=]() {
+                        return connectToUds(addr.c_str());
+                    });
+                    if (status == OK) goto success;
                     break;
                 case SocketType::UNIX:
-                    if (session->setupUnixDomainClient(addr.c_str())) goto success;
+                    status = session->setupUnixDomainClient(addr.c_str());
+                    if (status == OK) goto success;
                     break;
                 case SocketType::VSOCK:
-                    if (session->setupVsockClient(VMADDR_CID_LOCAL, vsockPort)) goto success;
+                    status = session->setupVsockClient(VMADDR_CID_LOCAL, vsockPort);
+                    if (status == OK) goto success;
                     break;
                 case SocketType::INET:
-                    if (session->setupInetClient("127.0.0.1", outPort)) goto success;
+                    status = session->setupInetClient("127.0.0.1", outPort);
+                    if (status == OK) goto success;
                     break;
                 default:
                     LOG_ALWAYS_FATAL("Unknown socket type");
             }
-            LOG_ALWAYS_FATAL("Could not connect");
+            LOG_ALWAYS_FATAL("Could not connect %s", statusToString(status).c_str());
         success:
             ret.sessions.push_back({session, session->getRootObject()});
         }
@@ -1191,14 +1196,14 @@ static bool testSupportVsockLoopback() {
     unsigned int vsockPort = allocateVsockPort();
     sp<RpcServer> server = RpcServer::make(RpcTransportCtxFactoryRaw::make());
     server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
-    CHECK(server->setupVsockServer(vsockPort));
+    CHECK_EQ(OK, server->setupVsockServer(vsockPort));
     server->start();
 
     sp<RpcSession> session = RpcSession::make(RpcTransportCtxFactoryRaw::make());
-    bool okay = session->setupVsockClient(VMADDR_CID_LOCAL, vsockPort);
+    status_t status = session->setupVsockClient(VMADDR_CID_LOCAL, vsockPort);
     while (!server->shutdown()) usleep(10000);
-    ALOGE("Detected vsock loopback supported: %d", okay);
-    return okay;
+    ALOGE("Detected vsock loopback supported: %s", statusToString(status).c_str());
+    return status == OK;
 }
 
 static std::vector<SocketType> testSocketTypes() {
@@ -1274,7 +1279,7 @@ TEST_P(BinderRpcSimple, Shutdown) {
     unlink(addr.c_str());
     auto server = RpcServer::make(newFactory(GetParam()));
     server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
-    ASSERT_TRUE(server->setupUnixDomainServer(addr.c_str()));
+    ASSERT_EQ(OK, server->setupUnixDomainServer(addr.c_str()));
     auto joinEnds = std::make_shared<OneOffSignal>();
 
     // If things are broken and the thread never stops, don't block other tests. Because the thread
@@ -1315,14 +1320,14 @@ TEST(BinderRpc, Java) {
     auto rpcServer = RpcServer::make();
     rpcServer->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
     unsigned int port;
-    ASSERT_TRUE(rpcServer->setupInetServer(kLocalInetAddress, 0, &port));
+    ASSERT_EQ(OK, rpcServer->setupInetServer(kLocalInetAddress, 0, &port));
     auto socket = rpcServer->releaseServer();
 
     auto keepAlive = sp<BBinder>::make();
     ASSERT_EQ(OK, binder->setRpcClientDebug(std::move(socket), keepAlive));
 
     auto rpcSession = RpcSession::make();
-    ASSERT_TRUE(rpcSession->setupInetClient("127.0.0.1", port));
+    ASSERT_EQ(OK, rpcSession->setupInetClient("127.0.0.1", port));
     auto rpcBinder = rpcSession->getRootObject();
     ASSERT_NE(nullptr, rpcBinder);
 
diff --git a/libs/binder/tests/parcel_fuzzer/random_parcel.cpp b/libs/binder/tests/parcel_fuzzer/random_parcel.cpp
index a2472f860e..8bf04ccae0 100644
--- a/libs/binder/tests/parcel_fuzzer/random_parcel.cpp
+++ b/libs/binder/tests/parcel_fuzzer/random_parcel.cpp
@@ -37,7 +37,7 @@ private:
 void fillRandomParcel(Parcel* p, FuzzedDataProvider&& provider) {
     if (provider.ConsumeBool()) {
         auto session = RpcSession::make(RpcTransportCtxFactoryRaw::make());
-        CHECK(session->addNullDebuggingClient());
+        CHECK_EQ(OK, session->addNullDebuggingClient());
         p->markForRpc(session);
         fillRandomParcelData(p, std::move(provider));
         return;
diff --git a/libs/binder/tests/rpc_fuzzer/main.cpp b/libs/binder/tests/rpc_fuzzer/main.cpp
index 9fc496f460..230f5c7b77 100644
--- a/libs/binder/tests/rpc_fuzzer/main.cpp
+++ b/libs/binder/tests/rpc_fuzzer/main.cpp
@@ -60,7 +60,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
     sp<RpcServer> server = RpcServer::make();
     server->setRootObject(sp<SomeBinder>::make());
     server->iUnderstandThisCodeIsExperimentalAndIWillNotUseItInProduction();
-    CHECK(server->setupUnixDomainServer(kSock.c_str()));
+    CHECK_EQ(OK, server->setupUnixDomainServer(kSock.c_str()));
 
     std::thread serverThread([=] { (void)server->join(); });