Merge "Fix heap-use-after-free issue flagged by fuzzer test." into main
diff --git a/media/mtp/MtpFfsHandle.cpp b/media/mtp/MtpFfsHandle.cpp
index 2ffd775..ef8c9aa 100644
--- a/media/mtp/MtpFfsHandle.cpp
+++ b/media/mtp/MtpFfsHandle.cpp
@@ -297,6 +297,10 @@
 }
 
 void MtpFfsHandle::close() {
+    auto timeout = std::chrono::seconds(2);
+    std::unique_lock lk(m);
+    cv.wait_for(lk, timeout ,[this]{return child_threads==0;});
+
     io_destroy(mCtx);
     closeEndpoints();
     closeConfig();
@@ -669,6 +673,11 @@
     char *temp = new char[me.length];
     memcpy(temp, me.data, me.length);
     me.data = temp;
+
+    std::unique_lock lk(m);
+    child_threads++;
+    lk.unlock();
+
     std::thread t([this, me]() { return this->doSendEvent(me); });
     t.detach();
     return 0;
@@ -680,6 +689,11 @@
     if (static_cast<unsigned>(ret) != length)
         PLOG(ERROR) << "Mtp error sending event thread!";
     delete[] reinterpret_cast<char*>(me.data);
+
+    std::unique_lock lk(m);
+    child_threads--;
+    lk.unlock();
+    cv.notify_one();
 }
 
 } // namespace android
diff --git a/media/mtp/MtpFfsHandle.h b/media/mtp/MtpFfsHandle.h
index e552e03..51cdef0 100644
--- a/media/mtp/MtpFfsHandle.h
+++ b/media/mtp/MtpFfsHandle.h
@@ -60,6 +60,10 @@
     bool mCanceled;
     bool mBatchCancel;
 
+    std::mutex m;
+    std::condition_variable cv;
+    std::atomic<int> child_threads{0};
+
     android::base::unique_fd mControl;
     // "in" from the host's perspective => sink for mtp server
     android::base::unique_fd mBulkIn;