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diff --git a/media/libvpx/libvpx/examples/vpx_dec_fuzzer.cc b/media/libvpx/libvpx/examples/vpx_dec_fuzzer.cc
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+/*
+ *  Copyright (c) 2018 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+/*
+ * Fuzzer for libvpx decoders
+ * ==========================
+ * Requirements
+ * --------------
+ * Requires Clang 6.0 or above as -fsanitize=fuzzer is used as a linker
+ * option.
+
+ * Steps to build
+ * --------------
+ * Clone libvpx repository
+   $git clone https://chromium.googlesource.com/webm/libvpx
+
+ * Create a directory in parallel to libvpx and change directory
+   $mkdir vpx_dec_fuzzer
+   $cd vpx_dec_fuzzer/
+
+ * Enable sanitizers (Supported: address integer memory thread undefined)
+   $source ../libvpx/tools/set_analyzer_env.sh address
+
+ * Configure libvpx.
+ * Note --size-limit and VPX_MAX_ALLOCABLE_MEMORY are defined to avoid
+ * Out of memory errors when running generated fuzzer binary
+   $../libvpx/configure --disable-unit-tests --size-limit=12288x12288 \
+   --extra-cflags="-fsanitize=fuzzer-no-link \
+   -DVPX_MAX_ALLOCABLE_MEMORY=1073741824" \
+   --disable-webm-io --enable-debug --disable-vp8-encoder \
+   --disable-vp9-encoder --disable-examples
+
+ * Build libvpx
+   $make -j32
+
+ * Build vp9 fuzzer
+   $ $CXX $CXXFLAGS -std=gnu++11 -DDECODER=vp9 \
+   -fsanitize=fuzzer -I../libvpx -I. -Wl,--start-group \
+   ../libvpx/examples/vpx_dec_fuzzer.cc -o ./vpx_dec_fuzzer_vp9 \
+   ./libvpx.a -Wl,--end-group
+
+ * DECODER should be defined as vp9 or vp8 to enable vp9/vp8
+ *
+ * create a corpus directory and copy some ivf files there.
+ * Based on which codec (vp8/vp9) is being tested, it is recommended to
+ * have corresponding ivf files in corpus directory
+ * Empty corpus directoy also is acceptable, though not recommended
+   $mkdir CORPUS && cp some-files CORPUS
+
+ * Run fuzzing:
+   $./vpx_dec_fuzzer_vp9 CORPUS
+
+ * References:
+ * http://llvm.org/docs/LibFuzzer.html
+ * https://github.com/google/oss-fuzz
+ */
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <algorithm>
+#include <memory>
+
+#include "vpx/vp8dx.h"
+#include "vpx/vpx_decoder.h"
+#include "vpx_ports/mem_ops.h"
+
+#define IVF_FRAME_HDR_SZ (4 + 8) /* 4 byte size + 8 byte timestamp */
+#define IVF_FILE_HDR_SZ 32
+
+#define VPXD_INTERFACE(name) VPXD_INTERFACE_(name)
+#define VPXD_INTERFACE_(name) vpx_codec_##name##_dx()
+
+extern "C" void usage_exit(void) { exit(EXIT_FAILURE); }
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+  if (size <= IVF_FILE_HDR_SZ) {
+    return 0;
+  }
+
+  vpx_codec_ctx_t codec;
+  // Set thread count in the range [1, 64].
+  const unsigned int threads = (data[IVF_FILE_HDR_SZ] & 0x3f) + 1;
+  vpx_codec_dec_cfg_t cfg = { threads, 0, 0 };
+  if (vpx_codec_dec_init(&codec, VPXD_INTERFACE(DECODER), &cfg, 0)) {
+    return 0;
+  }
+
+  if (threads > 1) {
+    const int enable = (data[IVF_FILE_HDR_SZ] & 0xa0) != 0;
+    const vpx_codec_err_t err =
+        vpx_codec_control(&codec, VP9D_SET_LOOP_FILTER_OPT, enable);
+    static_cast<void>(err);
+  }
+
+  data += IVF_FILE_HDR_SZ;
+  size -= IVF_FILE_HDR_SZ;
+
+  while (size > IVF_FRAME_HDR_SZ) {
+    size_t frame_size = mem_get_le32(data);
+    size -= IVF_FRAME_HDR_SZ;
+    data += IVF_FRAME_HDR_SZ;
+    frame_size = std::min(size, frame_size);
+
+    const vpx_codec_err_t err =
+        vpx_codec_decode(&codec, data, frame_size, nullptr, 0);
+    static_cast<void>(err);
+    vpx_codec_iter_t iter = nullptr;
+    vpx_image_t *img = nullptr;
+    while ((img = vpx_codec_get_frame(&codec, &iter)) != nullptr) {
+    }
+    data += frame_size;
+    size -= frame_size;
+  }
+  vpx_codec_destroy(&codec);
+  return 0;
+}