Fix code relying on undocumented SimpleAtoi quirk, which caused rollback

net/tools/quic/quic_spdy_server_stream.cc

 // Copyright (c) 2012 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 "net/tools/quic/quic_spdy_server_stream.h"
 
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_piece.h"
 #include "net/quic/quic_data_stream.h"
 #include "net/quic/quic_spdy_session.h"
 #include "net/quic/spdy_utils.h"
 #include "net/spdy/spdy_protocol.h"
 #include "net/tools/quic/quic_in_memory_cache.h"
 
 using base::StringPiece;
 using base::StringToInt;
 using std::string;
 
@@ skipping 70 matching lines @@
                                                data_len,
                                                &request_headers_);
   DCHECK_LE(len, data_len);
   if (len == 0 || request_headers_.empty()) {
     return false;  // Headers were invalid.
   }
 
   if (data_len > len) {
     body_.append(data + len, data_len - len);
   }
-  if (ContainsKey(request_headers_, "content-length") &&
-      !StringToInt(request_headers_["content-length"], &content_length_)) {
-    return false;  // Invalid content-length.
+  if (ContainsKey(request_headers_, "content-length")) {
+    // Historically, if an input to SimpleAtoi contained null byte, anything
+    // past it would be silently ignored. This behavior is being removed, but
+    // this method relies on it (see cl/101239633). Hence, we explicitly call
+    // c_str() on request headers to simulate the old behavior.
+    // TODO(rch): Correctly handle null-separated value in content-length.
+    // b/23554022
+    StringPiece trimmed_header(request_headers_["content-length"].c_str());
+    if (!StringToInt(trimmed_header, &content_length_)) {
+      return false;  // Invalid content-length.
+    }
   }
   return true;
 }
 
 void QuicSpdyServerStream::SendResponse() {
   if (!ContainsKey(request_headers_, GetHostKey()) ||
       !ContainsKey(request_headers_, ":path")) {
     SendErrorResponse();
     return;
   }
@@ skipping 57 matching lines @@
   }
 }
 
 const string QuicSpdyServerStream::GetHostKey() {
   // SPDY/4 uses ":authority" instead of ":host".
   return version() > QUIC_VERSION_24 ? ":authority" : ":host";
 }
 
 }  // namespace tools
 }  // namespace net