Use upstream libpng fuzz target.

projects/libpng/build.sh

@@ -31,7 +31,7 @@ make -j$(nproc) libpng16.la
 
 # build libpng_read_fuzzer.
 $CXX $CXXFLAGS -std=c++11 -I. \
-     $SRC/libpng_read_fuzzer.cc -o $OUT/libpng_read_fuzzer \
+     $SRC/libpng/contrib/oss-fuzz/libpng_read_fuzzer.cc -o $OUT/libpng_read_fuzzer \
      -lFuzzingEngine .libs/libpng16.a -lz
 
 # add seed corpus.

projects/libpng/libpng_read_fuzzer.cc

@@ -1,130 +0,0 @@
-// Copyright 2015 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 <stddef.h>
-#include <stdint.h>
-#include <string.h>
-
-#include <vector>
-
-#define PNG_INTERNAL
-#include "png.h"
-
-#define PNG_CLEANUP \
-    png_destroy_read_struct(&png_handler.png_ptr, &png_handler.info_ptr,\
-      nullptr);
-
-struct BufState {
-  const uint8_t* data;
-  size_t bytes_left;
-};
-
-struct PngObjectHandler {
-  png_infop info_ptr = nullptr;
-  png_structp png_ptr = nullptr;
-  png_voidp row_ptr = nullptr;
-  BufState* buf_state = nullptr;
-
-  ~PngObjectHandler() {
-    if (row_ptr && png_ptr) {
-      png_free(png_ptr, row_ptr);
-    }
-    if (png_ptr && info_ptr) {
-      png_destroy_read_struct(&png_ptr, &info_ptr, nullptr);
-    }
-    delete buf_state;
-  }
-};
-
-void user_read_data(png_structp png_ptr, png_bytep data, png_size_t length) {
-  BufState* buf_state = static_cast<BufState*>(png_get_io_ptr(png_ptr));
-  if (length > buf_state->bytes_left) {
-    png_error(png_ptr, "read error");
-  }
-  memcpy(data, buf_state->data, length);
-  buf_state->bytes_left -= length;
-  buf_state->data += length;
-}
-
-static const int kPngHeaderSize = 8;
-
-// Entry point for LibFuzzer.
-// Roughly follows the libpng book example:
-// http://www.libpng.org/pub/png/book/chapter13.html
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-  if (size < kPngHeaderSize) {
-    return 0;
-  }
-
-  std::vector<unsigned char> v(data, data + size);
-  if (png_sig_cmp(v.data(), 0, kPngHeaderSize)) {
-    // not a PNG.
-    return 0;
-  }
-
-  PngObjectHandler png_handler;
-  png_handler.png_ptr = png_create_read_struct
-    (PNG_LIBPNG_VER_STRING, nullptr, nullptr, nullptr);
-  if (!png_handler.png_ptr) {
-    return 0;
-  }
-
-  png_set_crc_action(png_handler.png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE);
-
-  png_handler.info_ptr = png_create_info_struct(png_handler.png_ptr);
-  if (!png_handler.info_ptr) {
-    return 0;
-  }
-
-  // Setting up reading from buffer.
-  png_handler.buf_state = new BufState();
-  png_handler.buf_state->data = data + kPngHeaderSize;
-  png_handler.buf_state->bytes_left = size - kPngHeaderSize;
-  png_set_read_fn(png_handler.png_ptr, png_handler.buf_state, user_read_data);
-  png_set_sig_bytes(png_handler.png_ptr, kPngHeaderSize);
-
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  // Reading.
-  png_read_info(png_handler.png_ptr, png_handler.info_ptr);
-  png_handler.row_ptr = png_malloc(
-      png_handler.png_ptr, png_get_rowbytes(png_handler.png_ptr,
-                                               png_handler.info_ptr));
-
-  // reset error handler to put png_deleter into scope.
-  if (setjmp(png_jmpbuf(png_handler.png_ptr))) {
-    PNG_CLEANUP
-    return 0;
-  }
-
-  png_uint_32 width, height;
-  int bit_depth, color_type, interlace_type, compression_type;
-  int filter_type;
-
-  if (!png_get_IHDR(png_handler.png_ptr, png_handler.info_ptr, &width,
-                    &height, &bit_depth, &color_type, &interlace_type,
-                    &compression_type, &filter_type)) {
-    return 0;
-  }
-
-  // This is going to be too slow.
-  if (width && height > 100000000 / width)
-    return 0;
-
-  int passes = png_set_interlace_handling(png_handler.png_ptr);
-  png_start_read_image(png_handler.png_ptr);
-
-  for (int pass = 0; pass < passes; ++pass) {
-    for (png_uint_32 y = 0; y < height; ++y) {
-      png_read_row(png_handler.png_ptr,
-                   static_cast<png_bytep>(png_handler.row_ptr), nullptr);
-    }
-  }
-
-  PNG_CLEANUP
-  return 0;
-}