Fix net::BrotliSourceStream to ignore trailing data.

net/filter/brotli_source_stream.cc

 // Copyright 2016 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/filter/brotli_source_stream.h"
 
 #include "base/bind.h"
 #include "base/bit_cast.h"
 #include "base/logging.h"
 #include "base/macros.h"
@@ skipping 75 matching lines @@
 
   // SourceStream implementation
   std::string GetTypeAsString() const override { return kBrotli; }
 
   int FilterData(IOBuffer* output_buffer,
                  int output_buffer_size,
                  IOBuffer* input_buffer,
                  int input_buffer_size,
                  int* consumed_bytes,
                  bool /*upstream_eof_reached*/) override {
+    if (decoding_status_ == DecodingStatus::DECODING_DONE) {
+      *consumed_bytes = input_buffer_size;
+      return OK;
+    }
+
+    if (decoding_status_ != DecodingStatus::DECODING_IN_PROGRESS)
+      return ERR_CONTENT_DECODING_FAILED;
+
     const uint8_t* next_in = bit_cast<uint8_t*>(input_buffer->data());
     size_t available_in = input_buffer_size;
     uint8_t* next_out = bit_cast<uint8_t*>(output_buffer->data());
     size_t available_out = output_buffer_size;
     size_t total_out = 0;
     // Check if start of the input stream looks like gzip stream.
     for (size_t i = consumed_bytes_; i < sizeof(kGzipHeader); ++i) {
       if (!gzip_header_detected_)
         break;
       size_t j = i - consumed_bytes_;
@@ skipping 12 matching lines @@
     produced_bytes_ += bytes_written;
     consumed_bytes_ += bytes_used;
 
     *consumed_bytes = bytes_used;
 
     switch (result) {
       case BROTLI_RESULT_NEEDS_MORE_OUTPUT:
         return bytes_written;
       case BROTLI_RESULT_SUCCESS:
         decoding_status_ = DecodingStatus::DECODING_DONE;
+        // Consume remaining bytes to avoid DCHECK in FilterSourceStream.
+        // See crbug.com/659311.
+        *consumed_bytes = input_buffer_size;
         return bytes_written;
       case BROTLI_RESULT_NEEDS_MORE_INPUT:
         // Decompress needs more input has consumed all existing input.
         DCHECK_EQ(*consumed_bytes, input_buffer_size);
         decoding_status_ = DecodingStatus::DECODING_IN_PROGRESS;
         return bytes_written;
       // If the decompressor threw an error, fail synchronously.
       default:
         decoding_status_ = DecodingStatus::DECODING_ERROR;
         return ERR_CONTENT_DECODING_FAILED;
@@ skipping 44 matching lines @@
 };
 
 }  // namespace
 
 std::unique_ptr<FilterSourceStream> CreateBrotliSourceStream(
     std::unique_ptr<SourceStream> previous) {
   return base::WrapUnique(new BrotliSourceStream(std::move(previous)));
 }
 
 }  // namespace net