Make HidConnection::Read reentrancy safe

device/hid/hid_connection_linux.cc

Index: device/hid/hid_connection_linux.cc
diff --git a/device/hid/hid_connection_linux.cc b/device/hid/hid_connection_linux.cc
index ec348ed6abc4cc5a429f74bd65c012c0ba0b096e..62d06c35d6a7610d9227ac6b918774e2658b9105 100644
--- a/device/hid/hid_connection_linux.cc
+++ b/device/hid/hid_connection_linux.cc
@@ -242,6 +242,12 @@ void HidConnectionLinux::PlatformSendFeatureReport(
 void HidConnectionLinux::ProcessInputReport(scoped_refptr<net::IOBuffer> buffer,
                                             size_t size) {
   DCHECK(thread_checker().CalledOnValidThread());
+  DCHECK_GE(size, 1u);
+
+  uint8_t report_id = buffer->data()[0];
+  if (IsReportIdProtected(report_id))
+    return;
+
   PendingHidReport report;
   report.buffer = buffer;
   report.size = size;
@@ -251,13 +257,17 @@ void HidConnectionLinux::ProcessInputReport(scoped_refptr<net::IOBuffer> buffer,
 
 void HidConnectionLinux::ProcessReadQueue() {
   DCHECK(thread_checker().CalledOnValidThread());
+
+  // Hold a reference to |this| to prevent a callback from freeing this object
+  // during the loop.
+  scoped_refptr<HidConnectionLinux> self(this);
   while (pending_reads_.size() && pending_reports_.size()) {
     PendingHidRead read = pending_reads_.front();
     PendingHidReport report = pending_reports_.front();
 
+    pending_reads_.pop();
     pending_reports_.pop();
-    if (CompleteRead(report.buffer, report.size, read.callback))
-      pending_reads_.pop();
+    read.callback.Run(true, report.buffer, report.size);
   }
 }