commit b0dd1184f0856a429b6efad0a47818331957b447
author Steven Moreland <smoreland@google.com> Tue May 25 01:56:46 2021 +0000
committer Steven Moreland <smoreland@google.com> Tue May 25 02:42:10 2021 +0000
tree 819ac03c162a21d287dada8c7a64b7116581e328
parent 1e4c2b81cc0e7310836cc5c892b0f01ad57fea95

libbinder: RpcSession check no shutdown trigger

If a pipe can't be created, this will fail. This error would result in
creating a session which can't be shutdown.

Bug: 185167543
Test: binderRpcTest
Change-Id: Id80da21cdc125783ea744c09fb864a5dc5771464

libs/binder/RpcSession.cpp

diff --git a/libs/binder/RpcSession.cpp b/libs/binder/RpcSession.cpp
index ac7544f..d05b848 100644
--- a/libs/binder/RpcSession.cpp
+++ b/libs/binder/RpcSession.cpp
@@ -86,8 +86,7 @@
         return false;
     }
 
-    addClientConnection(std::move(serverFd));
-    return true;
+    return addClientConnection(std::move(serverFd));
 }
 
 sp<IBinder> RpcSession::getRootObject() {
@@ -312,24 +311,25 @@
 
         LOG_RPC_DETAIL("Socket at %s client with fd %d", addr.toString().c_str(), serverFd.get());
 
-        addClientConnection(std::move(serverFd));
-        return true;
+        return addClientConnection(std::move(serverFd));
     }
 
     ALOGE("Ran out of retries to connect to %s", addr.toString().c_str());
     return false;
 }
 
-void RpcSession::addClientConnection(unique_fd fd) {
+bool RpcSession::addClientConnection(unique_fd fd) {
     std::lock_guard<std::mutex> _l(mMutex);
 
     if (mShutdownTrigger == nullptr) {
         mShutdownTrigger = FdTrigger::make();
+        if (mShutdownTrigger == nullptr) return false;
     }
 
     sp<RpcConnection> session = sp<RpcConnection>::make();
     session->fd = std::move(fd);
     mClientConnections.push_back(session);
+    return true;
 }
 
 void RpcSession::setForServer(const wp<RpcServer>& server, int32_t sessionId,

libs/binder/include/binder/RpcSession.h

diff --git a/libs/binder/include/binder/RpcSession.h b/libs/binder/include/binder/RpcSession.h
index 7c7feaa..4401aaf 100644
--- a/libs/binder/include/binder/RpcSession.h
+++ b/libs/binder/include/binder/RpcSession.h
@@ -102,6 +102,7 @@
 
     /** This is not a pipe. */
     struct FdTrigger {
+        /** Returns nullptr for error case */
         static std::unique_ptr<FdTrigger> make();
 
         /**
@@ -155,7 +156,7 @@
 
     bool setupSocketClient(const RpcSocketAddress& address);
     bool setupOneSocketClient(const RpcSocketAddress& address, int32_t sessionId);
-    void addClientConnection(base::unique_fd fd);
+    bool addClientConnection(base::unique_fd fd);
     void setForServer(const wp<RpcServer>& server, int32_t sessionId,
                       const std::shared_ptr<FdTrigger>& shutdownTrigger);
     sp<RpcConnection> assignServerToThisThread(base::unique_fd fd);