Make HidConnection::Read reentrancy safe

device/hid/hid_connection_win.cc

 // Copyright (c) 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/hid/hid_connection_win.h"
 
 #include <cstring>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 161 matching lines @@
                                       const ReadCallback& callback,
                                       PendingHidTransfer* transfer_raw,
                                       bool signaled) {
   if (!file_.IsValid()) {
     callback.Run(false, nullptr, 0);
     return;
   }
 
   std::unique_ptr<PendingHidTransfer> transfer = UnlinkTransfer(transfer_raw);
   DWORD bytes_transferred;
-  if (signaled && GetOverlappedResult(file_.Get(), transfer->GetOverlapped(),
-                                      &bytes_transferred, FALSE)) {
-    CompleteRead(buffer, bytes_transferred, callback);
-  } else {
+  if (!signaled || !GetOverlappedResult(file_.Get(), transfer->GetOverlapped(),
+                                        &bytes_transferred, FALSE)) {
     HID_PLOG(EVENT) << "HID read failed";
     callback.Run(false, nullptr, 0);
+    return;
   }
+
+  if (bytes_transferred < 1) {
+    HID_LOG(EVENT) << "HID read too short.";
+    callback.Run(false, nullptr, 0);
+    return;
+  }
+
+  uint8_t report_id = buffer->data()[0];
+  if (IsReportIdProtected(report_id)) {
+    PlatformRead(callback);
+    return;
+  }
+
+  callback.Run(true, buffer, bytes_transferred);
 }
 
 void HidConnectionWin::OnReadFeatureComplete(
     scoped_refptr<net::IOBuffer> buffer,
     const ReadCallback& callback,
     PendingHidTransfer* transfer_raw,
     bool signaled) {
   if (!file_.IsValid()) {
     callback.Run(false, nullptr, 0);
     return;
@@ skipping 36 matching lines @@
       [transfer](const std::unique_ptr<PendingHidTransfer>& this_transfer) {
         return transfer == this_transfer.get();
       });
   DCHECK(it != transfers_.end());
   std::unique_ptr<PendingHidTransfer> saved_transfer = std::move(*it);
   transfers_.erase(it);
   return saved_transfer;
 }
 
 }  // namespace device