/* * Copyright 2016 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "Fuzz.h" #include "SkCanvas.h" #include "SkCodec.h" #include "SkCommandLineFlags.h" #include "SkData.h" #include "SkImage.h" #include "SkImageEncoder.h" #include "SkMallocPixelRef.h" #include "SkOSFile.h" #include "SkOSPath.h" #include "SkPaint.h" #include "SkPath.h" #include "SkPicturePriv.h" #include "SkReadBuffer.h" #include "SkStream.h" #include "SkSurface.h" #include "SkTextBlob.h" #include "sk_tool_utils.h" #include <iostream> #include <map> #include <regex> #include <signal.h> DEFINE_string2(bytes, b, "", "A path to a file or a directory. If a file, the " "contents will be used as the fuzz bytes. If a directory, all files " "in the directory will be used as fuzz bytes for the fuzzer, one at a " "time."); DEFINE_string2(name, n, "", "If --type is 'api', fuzz the API with this name."); DEFINE_string2(dump, d, "", "If not empty, dump 'image*' or 'skp' types as a " "PNG with this name."); DEFINE_bool2(verbose, v, false, "Print more information while fuzzing."); // This cannot be inlined in DEFINE_string2 due to interleaved ifdefs static constexpr char g_type_message[] = "How to interpret --bytes, one of:\n" "android_codec\n" "animated_image_decode\n" "api\n" "color_deserialize\n" "filter_fuzz (equivalent to Chrome's filter_fuzz_stub)\n" "image_decode\n" "image_decode_incremental\n" "image_mode\n" "image_scale\n" "json\n" "path_deserialize\n" "region_deserialize\n" "region_set_path\n" "skp\n" "sksl2glsl\n" "sksl2metal\n" "sksl2spirv\n" #if defined(SK_ENABLE_SKOTTIE) "skottie_json\n" #endif "textblob"; DEFINE_string2(type, t, "", g_type_message); static int fuzz_file(SkString path, SkString type); static uint8_t calculate_option(SkData*); static SkString try_auto_detect(SkString path, SkString* name); static void fuzz_android_codec(sk_sp<SkData>); static void fuzz_animated_img(sk_sp<SkData>); static void fuzz_api(sk_sp<SkData> bytes, SkString name); static void fuzz_color_deserialize(sk_sp<SkData>); static void fuzz_filter_fuzz(sk_sp<SkData>); static void fuzz_image_decode(sk_sp<SkData>); static void fuzz_image_decode_incremental(sk_sp<SkData>); static void fuzz_img(sk_sp<SkData>, uint8_t, uint8_t); static void fuzz_json(sk_sp<SkData>); static void fuzz_path_deserialize(sk_sp<SkData>); static void fuzz_region_deserialize(sk_sp<SkData>); static void fuzz_region_set_path(sk_sp<SkData>); static void fuzz_skp(sk_sp<SkData>); static void fuzz_sksl2glsl(sk_sp<SkData>); static void fuzz_sksl2metal(sk_sp<SkData>); static void fuzz_sksl2spirv(sk_sp<SkData>); static void fuzz_textblob_deserialize(sk_sp<SkData>); static void print_api_names(); #if defined(SK_ENABLE_SKOTTIE) static void fuzz_skottie_json(sk_sp<SkData>); #endif int main(int argc, char** argv) { SkCommandLineFlags::SetUsage("Usage: fuzz -t <type> -b <path/to/file> [-n api-to-fuzz]\n" " fuzz -b <path/to/file>\n" "--help lists the valid types. If type is not specified,\n" "fuzz will make a guess based on the name of the file.\n"); SkCommandLineFlags::Parse(argc, argv); SkString path = SkString(FLAGS_bytes.isEmpty() ? argv[0] : FLAGS_bytes[0]); SkString type = SkString(FLAGS_type.isEmpty() ? "" : FLAGS_type[0]); if (!sk_isdir(path.c_str())) { return fuzz_file(path, type); } SkOSFile::Iter it(path.c_str()); for (SkString file; it.next(&file); ) { SkString p = SkOSPath::Join(path.c_str(), file.c_str()); SkDebugf("Fuzzing %s\n", p.c_str()); int rv = fuzz_file(p, type); if (rv != 0) { return rv; } } return 0; } static int fuzz_file(SkString path, SkString type) { sk_sp<SkData> bytes(SkData::MakeFromFileName(path.c_str())); if (!bytes) { SkDebugf("Could not read %s\n", path.c_str()); return 1; } SkString name = SkString(FLAGS_name.isEmpty() ? "" : FLAGS_name[0]); if (type.isEmpty()) { type = try_auto_detect(path, &name); } if (type.isEmpty()) { SkDebugf("Could not autodetect type of %s\n", path.c_str()); return 1; } if (type.equals("android_codec")) { fuzz_android_codec(bytes); return 0; } if (type.equals("animated_image_decode")) { fuzz_animated_img(bytes); return 0; } if (type.equals("api")) { fuzz_api(bytes, name); return 0; } if (type.equals("color_deserialize")) { fuzz_color_deserialize(bytes); return 0; } if (type.equals("filter_fuzz")) { fuzz_filter_fuzz(bytes); return 0; } if (type.equals("image_decode")) { fuzz_image_decode(bytes); return 0; } if (type.equals("image_decode_incremental")) { fuzz_image_decode_incremental(bytes); return 0; } if (type.equals("image_scale")) { uint8_t option = calculate_option(bytes.get()); fuzz_img(bytes, option, 0); return 0; } if (type.equals("image_mode")) { uint8_t option = calculate_option(bytes.get()); fuzz_img(bytes, 0, option); return 0; } if (type.equals("json")) { fuzz_json(bytes); return 0; } if (type.equals("path_deserialize")) { fuzz_path_deserialize(bytes); return 0; } if (type.equals("region_deserialize")) { fuzz_region_deserialize(bytes); return 0; } if (type.equals("region_set_path")) { fuzz_region_set_path(bytes); return 0; } if (type.equals("pipe")) { SkDebugf("I would prefer not to.\n"); return 0; } #if defined(SK_ENABLE_SKOTTIE) if (type.equals("skottie_json")) { fuzz_skottie_json(bytes); return 0; } #endif if (type.equals("skp")) { fuzz_skp(bytes); return 0; } if (type.equals("sksl2glsl")) { fuzz_sksl2glsl(bytes); return 0; } if (type.equals("sksl2metal")) { fuzz_sksl2metal(bytes); return 0; } if (type.equals("sksl2spirv")) { fuzz_sksl2spirv(bytes); return 0; } if (type.equals("textblob")) { fuzz_textblob_deserialize(bytes); return 0; } SkDebugf("Unknown type %s\n", type.c_str()); SkCommandLineFlags::PrintUsage(); return 1; } static std::map<std::string, std::string> cf_api_map = { {"api_draw_functions", "DrawFunctions"}, {"api_gradients", "Gradients"}, {"api_image_filter", "ImageFilter"}, {"api_mock_gpu_canvas", "MockGPUCanvas"}, {"api_null_canvas", "NullCanvas"}, {"api_path_measure", "PathMeasure"}, {"api_pathop", "Pathop"}, {"api_polyutils", "PolyUtils"}, {"api_raster_n32_canvas", "RasterN32Canvas"}, {"jpeg_encoder", "JPEGEncoder"}, {"png_encoder", "PNGEncoder"}, {"skia_pathop_fuzzer", "LegacyChromiumPathop"}, {"webp_encoder", "WEBPEncoder"} }; // maps clusterfuzz/oss-fuzz -> Skia's name static std::map<std::string, std::string> cf_map = { {"android_codec", "android_codec"}, {"animated_image_decode", "animated_image_decode"}, {"image_decode", "image_decode"}, {"image_decode_incremental", "image_decode_incremental"}, {"image_filter_deserialize", "filter_fuzz"}, {"image_filter_deserialize_width", "filter_fuzz"}, {"path_deserialize", "path_deserialize"}, {"region_deserialize", "region_deserialize"}, {"region_set_path", "region_set_path"}, {"skjson", "json"}, {"sksl2glsl", "sksl2glsl"}, {"sksl2metal", "sksl2metal"}, {"sksl2spirv", "sksl2spirv"}, #if defined(SK_ENABLE_SKOTTIE) {"skottie_json", "skottie_json"}, #endif {"textblob_deserialize", "textblob"} }; static SkString try_auto_detect(SkString path, SkString* name) { std::cmatch m; std::regex clusterfuzz("clusterfuzz-testcase(-minimized)?-([a-z0-9_]+)-[\\d]+"); std::regex skiafuzzer("(api-)?(\\w+)-[a-f0-9]+"); if (std::regex_search(path.c_str(), m, clusterfuzz)) { std::string type = m.str(2); if (cf_api_map.find(type) != cf_api_map.end()) { *name = SkString(cf_api_map[type].c_str()); return SkString("api"); } else { if (cf_map.find(type) != cf_map.end()) { return SkString(cf_map[type].c_str()); } } } else if (std::regex_search(path.c_str(), m, skiafuzzer)) { std::string a1 = m.str(1); std::string typeOrName = m.str(2); if (a1.length() > 0) { // it's an api fuzzer *name = SkString(typeOrName.c_str()); return SkString("api"); } else { return SkString(typeOrName.c_str()); } } return SkString(""); } void FuzzJSON(sk_sp<SkData> bytes); static void fuzz_json(sk_sp<SkData> bytes){ FuzzJSON(bytes); SkDebugf("[terminated] Done parsing!\n"); } #if defined(SK_ENABLE_SKOTTIE) void FuzzSkottieJSON(sk_sp<SkData> bytes); static void fuzz_skottie_json(sk_sp<SkData> bytes){ FuzzSkottieJSON(bytes); SkDebugf("[terminated] Done animating!\n"); } #endif // This adds up the first 1024 bytes and returns it as an 8 bit integer. This allows afl-fuzz to // deterministically excercise different paths, or *options* (such as different scaling sizes or // different image modes) without needing to introduce a parameter. This way we don't need a // image_scale1, image_scale2, image_scale4, etc fuzzer, we can just have a image_scale fuzzer. // Clients are expected to transform this number into a different range, e.g. with modulo (%). static uint8_t calculate_option(SkData* bytes) { uint8_t total = 0; const uint8_t* data = bytes->bytes(); for (size_t i = 0; i < 1024 && i < bytes->size(); i++) { total += data[i]; } return total; } static void print_api_names(){ SkDebugf("When using --type api, please choose an API to fuzz with --name/-n:\n"); for (const Fuzzable& fuzzable : sk_tools::Registry<Fuzzable>::Range()) { SkDebugf("\t%s\n", fuzzable.name); } } static void fuzz_api(sk_sp<SkData> bytes, SkString name) { for (const Fuzzable& fuzzable : sk_tools::Registry<Fuzzable>::Range()) { if (name.equals(fuzzable.name)) { SkDebugf("Fuzzing %s...\n", fuzzable.name); Fuzz fuzz(std::move(bytes)); fuzzable.fn(&fuzz); SkDebugf("[terminated] Success!\n"); return; } } print_api_names(); } static void dump_png(SkBitmap bitmap) { if (!FLAGS_dump.isEmpty()) { sk_tool_utils::EncodeImageToFile(FLAGS_dump[0], bitmap, SkEncodedImageFormat::kPNG, 100); SkDebugf("Dumped to %s\n", FLAGS_dump[0]); } } bool FuzzAnimatedImage(sk_sp<SkData> bytes); static void fuzz_animated_img(sk_sp<SkData> bytes) { if (FuzzAnimatedImage(bytes)) { SkDebugf("[terminated] Success from decoding/drawing animated image!\n"); return; } SkDebugf("[terminated] Could not decode or draw animated image.\n"); } bool FuzzImageDecode(sk_sp<SkData> bytes); static void fuzz_image_decode(sk_sp<SkData> bytes) { if (FuzzImageDecode(bytes)) { SkDebugf("[terminated] Success from decoding/drawing image!\n"); return; } SkDebugf("[terminated] Could not decode or draw image.\n"); } bool FuzzIncrementalImageDecode(sk_sp<SkData> bytes); static void fuzz_image_decode_incremental(sk_sp<SkData> bytes) { if (FuzzIncrementalImageDecode(bytes)) { SkDebugf("[terminated] Success using incremental decode!\n"); return; } SkDebugf("[terminated] Could not incrementally decode and image.\n"); } bool FuzzAndroidCodec(sk_sp<SkData> bytes, uint8_t sampleSize); static void fuzz_android_codec(sk_sp<SkData> bytes) { Fuzz fuzz(bytes); uint8_t sampleSize; fuzz.nextRange(&sampleSize, 1, 64); bytes = SkData::MakeSubset(bytes.get(), 1, bytes->size() - 1); if (FuzzAndroidCodec(bytes, sampleSize)) { SkDebugf("[terminated] Success on Android Codec sampleSize=%u!\n", sampleSize); return; } SkDebugf("[terminated] Could not use Android Codec sampleSize=%u!\n", sampleSize); } // This is a "legacy" fuzzer that likely does too much. It was based off of how // DM reads in images. image_decode, image_decode_incremental and android_codec // are more targeted fuzzers that do a subset of what this one does. static void fuzz_img(sk_sp<SkData> bytes, uint8_t scale, uint8_t mode) { // We can scale 1x, 2x, 4x, 8x, 16x scale = scale % 5; float fscale = (float)pow(2.0f, scale); SkDebugf("Scaling factor: %f\n", fscale); // We have 5 different modes of decoding. mode = mode % 5; SkDebugf("Mode: %d\n", mode); // This is mostly copied from DMSrcSink's CodecSrc::draw method. SkDebugf("Decoding\n"); std::unique_ptr<SkCodec> codec(SkCodec::MakeFromData(bytes)); if (nullptr == codec.get()) { SkDebugf("[terminated] Couldn't create codec.\n"); return; } SkImageInfo decodeInfo = codec->getInfo(); SkISize size = codec->getScaledDimensions(fscale); decodeInfo = decodeInfo.makeWH(size.width(), size.height()); SkBitmap bitmap; SkCodec::Options options; options.fZeroInitialized = SkCodec::kYes_ZeroInitialized; if (!bitmap.tryAllocPixelsFlags(decodeInfo, SkBitmap::kZeroPixels_AllocFlag)) { SkDebugf("[terminated] Could not allocate memory. Image might be too large (%d x %d)", decodeInfo.width(), decodeInfo.height()); return; } switch (mode) { case 0: {//kCodecZeroInit_Mode, kCodec_Mode switch (codec->getPixels(decodeInfo, bitmap.getPixels(), bitmap.rowBytes(), &options)) { case SkCodec::kSuccess: SkDebugf("[terminated] Success!\n"); break; case SkCodec::kIncompleteInput: SkDebugf("[terminated] Partial Success\n"); break; case SkCodec::kErrorInInput: SkDebugf("[terminated] Partial Success with error\n"); break; case SkCodec::kInvalidConversion: SkDebugf("Incompatible colortype conversion\n"); // Crash to allow afl-fuzz to know this was a bug. raise(SIGSEGV); default: SkDebugf("[terminated] Couldn't getPixels.\n"); return; } break; } case 1: {//kScanline_Mode if (SkCodec::kSuccess != codec->startScanlineDecode(decodeInfo)) { SkDebugf("[terminated] Could not start scanline decoder\n"); return; } void* dst = bitmap.getAddr(0, 0); size_t rowBytes = bitmap.rowBytes(); uint32_t height = decodeInfo.height(); // We do not need to check the return value. On an incomplete // image, memory will be filled with a default value. codec->getScanlines(dst, height, rowBytes); SkDebugf("[terminated] Success!\n"); break; } case 2: { //kStripe_Mode const int height = decodeInfo.height(); // This value is chosen arbitrarily. We exercise more cases by choosing a value that // does not align with image blocks. const int stripeHeight = 37; const int numStripes = (height + stripeHeight - 1) / stripeHeight; // Decode odd stripes if (SkCodec::kSuccess != codec->startScanlineDecode(decodeInfo) || SkCodec::kTopDown_SkScanlineOrder != codec->getScanlineOrder()) { // This mode was designed to test the new skip scanlines API in libjpeg-turbo. // Jpegs have kTopDown_SkScanlineOrder, and at this time, it is not interesting // to run this test for image types that do not have this scanline ordering. SkDebugf("[terminated] Could not start top-down scanline decoder\n"); return; } for (int i = 0; i < numStripes; i += 2) { // Skip a stripe const int linesToSkip = SkTMin(stripeHeight, height - i * stripeHeight); codec->skipScanlines(linesToSkip); // Read a stripe const int startY = (i + 1) * stripeHeight; const int linesToRead = SkTMin(stripeHeight, height - startY); if (linesToRead > 0) { codec->getScanlines(bitmap.getAddr(0, startY), linesToRead, bitmap.rowBytes()); } } // Decode even stripes const SkCodec::Result startResult = codec->startScanlineDecode(decodeInfo); if (SkCodec::kSuccess != startResult) { SkDebugf("[terminated] Failed to restart scanline decoder with same parameters.\n"); return; } for (int i = 0; i < numStripes; i += 2) { // Read a stripe const int startY = i * stripeHeight; const int linesToRead = SkTMin(stripeHeight, height - startY); codec->getScanlines(bitmap.getAddr(0, startY), linesToRead, bitmap.rowBytes()); // Skip a stripe const int linesToSkip = SkTMin(stripeHeight, height - (i + 1) * stripeHeight); if (linesToSkip > 0) { codec->skipScanlines(linesToSkip); } } SkDebugf("[terminated] Success!\n"); break; } case 3: { //kSubset_Mode // Arbitrarily choose a divisor. int divisor = 2; // Total width/height of the image. const int W = codec->getInfo().width(); const int H = codec->getInfo().height(); if (divisor > W || divisor > H) { SkDebugf("[terminated] Cannot codec subset: divisor %d is too big " "with dimensions (%d x %d)\n", divisor, W, H); return; } // subset dimensions // SkWebpCodec, the only one that supports subsets, requires even top/left boundaries. const int w = SkAlign2(W / divisor); const int h = SkAlign2(H / divisor); SkIRect subset; SkCodec::Options opts; opts.fSubset = ⊂ SkBitmap subsetBm; // We will reuse pixel memory from bitmap. void* pixels = bitmap.getPixels(); // Keep track of left and top (for drawing subsetBm into canvas). We could use // fscale * x and fscale * y, but we want integers such that the next subset will start // where the last one ended. So we'll add decodeInfo.width() and height(). int left = 0; for (int x = 0; x < W; x += w) { int top = 0; for (int y = 0; y < H; y+= h) { // Do not make the subset go off the edge of the image. const int preScaleW = SkTMin(w, W - x); const int preScaleH = SkTMin(h, H - y); subset.setXYWH(x, y, preScaleW, preScaleH); // And fscale // FIXME: Should we have a version of getScaledDimensions that takes a subset // into account? decodeInfo = decodeInfo.makeWH( SkTMax(1, SkScalarRoundToInt(preScaleW * fscale)), SkTMax(1, SkScalarRoundToInt(preScaleH * fscale))); size_t rowBytes = decodeInfo.minRowBytes(); if (!subsetBm.installPixels(decodeInfo, pixels, rowBytes)) { SkDebugf("[terminated] Could not install pixels.\n"); return; } const SkCodec::Result result = codec->getPixels(decodeInfo, pixels, rowBytes, &opts); switch (result) { case SkCodec::kSuccess: case SkCodec::kIncompleteInput: case SkCodec::kErrorInInput: SkDebugf("okay\n"); break; case SkCodec::kInvalidConversion: if (0 == (x|y)) { // First subset is okay to return unimplemented. SkDebugf("[terminated] Incompatible colortype conversion\n"); return; } // If the first subset succeeded, a later one should not fail. // fall through to failure case SkCodec::kUnimplemented: if (0 == (x|y)) { // First subset is okay to return unimplemented. SkDebugf("[terminated] subset codec not supported\n"); return; } // If the first subset succeeded, why would a later one fail? // fall through to failure default: SkDebugf("[terminated] subset codec failed to decode (%d, %d, %d, %d) " "with dimensions (%d x %d)\t error %d\n", x, y, decodeInfo.width(), decodeInfo.height(), W, H, result); return; } // translate by the scaled height. top += decodeInfo.height(); } // translate by the scaled width. left += decodeInfo.width(); } SkDebugf("[terminated] Success!\n"); break; } case 4: { //kAnimated_Mode std::vector<SkCodec::FrameInfo> frameInfos = codec->getFrameInfo(); if (frameInfos.size() == 0) { SkDebugf("[terminated] Not an animated image\n"); break; } for (size_t i = 0; i < frameInfos.size(); i++) { options.fFrameIndex = i; auto result = codec->startIncrementalDecode(decodeInfo, bitmap.getPixels(), bitmap.rowBytes(), &options); if (SkCodec::kSuccess != result) { SkDebugf("[terminated] failed to start incremental decode " "in frame %d with error %d\n", i, result); return; } result = codec->incrementalDecode(); if (result == SkCodec::kIncompleteInput || result == SkCodec::kErrorInInput) { SkDebugf("okay\n"); // Frames beyond this one will not decode. break; } if (result == SkCodec::kSuccess) { SkDebugf("okay - decoded frame %d\n", i); } else { SkDebugf("[terminated] incremental decode failed with " "error %d\n", result); return; } } SkDebugf("[terminated] Success!\n"); break; } default: SkDebugf("[terminated] Mode not implemented yet\n"); } dump_png(bitmap); } static void fuzz_skp(sk_sp<SkData> bytes) { SkReadBuffer buf(bytes->data(), bytes->size()); SkDebugf("Decoding\n"); sk_sp<SkPicture> pic(SkPicturePriv::MakeFromBuffer(buf)); if (!pic) { SkDebugf("[terminated] Couldn't decode as a picture.\n"); return; } SkDebugf("Rendering\n"); SkBitmap bitmap; if (!FLAGS_dump.isEmpty()) { SkIRect size = pic->cullRect().roundOut(); bitmap.allocN32Pixels(size.width(), size.height()); } SkCanvas canvas(bitmap); canvas.drawPicture(pic); SkDebugf("[terminated] Success! Decoded and rendered an SkPicture!\n"); dump_png(bitmap); } static void fuzz_color_deserialize(sk_sp<SkData> bytes) { sk_sp<SkColorSpace> space(SkColorSpace::Deserialize(bytes->data(), bytes->size())); if (!space) { SkDebugf("[terminated] Couldn't deserialize Colorspace.\n"); return; } SkDebugf("[terminated] Success! deserialized Colorspace.\n"); } void FuzzPathDeserialize(SkReadBuffer& buf); static void fuzz_path_deserialize(sk_sp<SkData> bytes) { SkReadBuffer buf(bytes->data(), bytes->size()); FuzzPathDeserialize(buf); SkDebugf("[terminated] path_deserialize didn't crash!\n"); } bool FuzzRegionDeserialize(sk_sp<SkData> bytes); static void fuzz_region_deserialize(sk_sp<SkData> bytes) { if (!FuzzRegionDeserialize(bytes)) { SkDebugf("[terminated] Couldn't initialize SkRegion.\n"); return; } SkDebugf("[terminated] Success! Initialized SkRegion.\n"); } void FuzzTextBlobDeserialize(SkReadBuffer& buf); static void fuzz_textblob_deserialize(sk_sp<SkData> bytes) { SkReadBuffer buf(bytes->data(), bytes->size()); FuzzTextBlobDeserialize(buf); SkDebugf("[terminated] textblob didn't crash!\n"); } void FuzzRegionSetPath(Fuzz* fuzz); static void fuzz_region_set_path(sk_sp<SkData> bytes) { Fuzz fuzz(bytes); FuzzRegionSetPath(&fuzz); SkDebugf("[terminated] region_set_path didn't crash!\n"); } void FuzzImageFilterDeserialize(sk_sp<SkData> bytes); static void fuzz_filter_fuzz(sk_sp<SkData> bytes) { FuzzImageFilterDeserialize(bytes); SkDebugf("[terminated] filter_fuzz didn't crash!\n"); } bool FuzzSKSL2GLSL(sk_sp<SkData> bytes); static void fuzz_sksl2glsl(sk_sp<SkData> bytes) { if (FuzzSKSL2GLSL(bytes)) { SkDebugf("[terminated] Success! Compiled input to GLSL.\n"); } else { SkDebugf("[terminated] Could not compile input to GLSL.\n"); } } bool FuzzSKSL2SPIRV(sk_sp<SkData> bytes); static void fuzz_sksl2spirv(sk_sp<SkData> bytes) { if (FuzzSKSL2SPIRV(bytes)) { SkDebugf("[terminated] Success! Compiled input to SPIRV.\n"); } else { SkDebugf("[terminated] Could not compile input to SPIRV.\n"); } } bool FuzzSKSL2Metal(sk_sp<SkData> bytes); static void fuzz_sksl2metal(sk_sp<SkData> bytes) { if (FuzzSKSL2Metal(bytes)) { SkDebugf("[terminated] Success! Compiled input to Metal.\n"); } else { SkDebugf("[terminated] Could not compile input to Metal.\n"); } }