// Copyright 2017 the V8 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. #include <limits.h> #include <stddef.h> #include <stdint.h> #include <functional> #include <string> #include "include/v8-exception.h" #include "include/v8-isolate.h" #include "include/v8-local-handle.h" #include "include/v8-primitive.h" #include "include/v8-script.h" #include "src/heap/factory.h" #include "src/objects/objects-inl.h" #include "src/regexp/regexp.h" #include "test/fuzzer/fuzzer-support.h" // This is a hexdump of test/fuzzer/regexp_builtins/mjsunit.js generated using // `xxd -i mjsunit.js`. It contains the `assertEquals` JS function used below. #include "test/fuzzer/regexp_builtins/mjsunit.js.h" namespace v8 { namespace internal { namespace { constexpr bool kVerbose = false; // For debugging, verbose error messages. constexpr uint32_t kRegExpBuiltinsFuzzerHashSeed = 83; #define REGEXP_BUILTINS(V) \ V(Exec, exec) \ V(Match, Symbol.match) \ V(Replace, Symbol.replace) \ V(Search, Symbol.search) \ V(Split, Symbol.split) \ V(Test, test) struct FuzzerArgs { FuzzerArgs(const uint8_t* input_data, size_t input_length, v8::Local<v8::Context> context, Isolate* isolate) : input_cursor(0), input_data(input_data), input_length(input_length), context(context), isolate(isolate) {} size_t input_cursor; const uint8_t* const input_data; const size_t input_length; v8::Local<v8::Context> context; Isolate* const isolate; }; enum RegExpBuiltin { #define CASE(name, ...) kRegExpPrototype##name, REGEXP_BUILTINS(CASE) #undef CASE kRegExpBuiltinCount, }; #define CASE(name, ...) void TestRegExpPrototype##name(FuzzerArgs* args); REGEXP_BUILTINS(CASE) #undef CASE v8::Local<v8::String> v8_str(v8::Isolate* isolate, const char* s) { return v8::String::NewFromUtf8(isolate, s).ToLocalChecked(); } v8::MaybeLocal<v8::Value> CompileRun(v8::Local<v8::Context> context, const char* source) { v8::Local<v8::Script> script; v8::MaybeLocal<v8::Script> maybe_script = v8::Script::Compile(context, v8_str(context->GetIsolate(), source)); if (!maybe_script.ToLocal(&script)) return v8::MaybeLocal<v8::Value>(); return script->Run(context); } uint8_t RandomByte(FuzzerArgs* args) { // Silently wraps to the beginning of input data. Ideally, input data should // be long enough to avoid that. const size_t index = args->input_cursor; CHECK(index < args->input_length); args->input_cursor = (index + 1) % args->input_length; return args->input_data[index]; } void CompileMjsunit(const FuzzerArgs* args) { std::string source( reinterpret_cast<const char*>(test_fuzzer_regexp_builtins_mjsunit_js), test_fuzzer_regexp_builtins_mjsunit_js_len); CompileRun(args->context, source.c_str()).ToLocalChecked(); } std::string NaiveEscape(const std::string& input, char escaped_char) { std::string out; for (size_t i = 0; i < input.size(); i++) { // Just omit newlines and \0 chars and naively replace other escaped chars. const char c = input[i]; if (c == '\r' || c == '\n' || c == '\0') continue; out += (input[i] == escaped_char) ? '_' : c; } // Disallow trailing backslashes as they mess with our naive source string // concatenation. if (!out.empty() && out.back() == '\\') out.back() = '_'; return out; } std::string GenerateRandomString(FuzzerArgs* args, size_t length) { // Limited to an ASCII subset for now. std::string s(length, '\0'); for (size_t i = 0; i < length; i++) { s[i] = static_cast<char>((RandomByte(args) % 0x5F) + 0x20); } return s; } std::string GenerateRandomPattern(FuzzerArgs* args) { const int kMaxPatternLength = 16; std::string s = GenerateRandomString(args, (RandomByte(args) % kMaxPatternLength) + 1); // A leading '*' would be a comment instead of a regexp literal. if (s[0] == '*') s[0] = '.'; return s; } std::string PickRandomPresetPattern(FuzzerArgs* args) { static const char* preset_patterns[] = { ".", // Always matches. "\\P{Any}", // Never matches. "^", // Zero-width assertion, matches once. "(?=.)", // Zero-width assertion, matches at every position. "\\b", // Zero-width assertion, matches at each word boundary. "()", // Zero-width assertion, matches at every position with groups. "(?<a>)", // Likewise but with named groups. "((((.).).).)", "(?<a>(?<b>(?<c>(?<d>.).).).)", // Copied from // https://cs.chromium.org/chromium/src/testing/libfuzzer/fuzzers/dicts/regexp.dict "?", "abc", "()", "[]", "abc|def", "abc|def|ghi", "^xxx$", "ab\\b\\d\\bcd", "\\w|\\d", "a*?", "abc+", "abc+?", "xyz?", "xyz??", "xyz{0,1}", "xyz{0,1}?", "xyz{93}", "xyz{1,32}", "xyz{1,32}?", "xyz{1,}", "xyz{1,}?", "a\\fb\\nc\\rd\\te\\vf", "a\\nb\\bc", "(?:foo)", "(?: foo )", "foo|(bar|baz)|quux", "foo(?=bar)baz", "foo(?!bar)baz", "foo(?<=bar)baz", "foo(?<!bar)baz", "()", "(?=)", "[]", "[x]", "[xyz]", "[a-zA-Z0-9]", "[-123]", "[^123]", "]", "}", "[a-b-c]", "[x\\dz]", "[\\d-z]", "[\\d-\\d]", "[z-\\d]", "\\cj\\cJ\\ci\\cI\\ck\\cK", "\\c!", "\\c_", "\\c~", "[\\c!]", "[\\c_]", "[\\c~]", "[\\ca]", "[\\cz]", "[\\cA]", "[\\cZ]", "[\\c1]", "\\[\\]\\{\\}\\(\\)\\%\\^\\#\\ ", "[\\[\\]\\{\\}\\(\\)\\%\\^\\#\\ ]", "\\8", "\\9", "\\11", "\\11a", "\\011", "\\118", "\\111", "\\1111", "(x)(x)(x)\\1", "(x)(x)(x)\\2", "(x)(x)(x)\\3", "(x)(x)(x)\\4", "(x)(x)(x)\\1*", "(x)(x)(x)\\3*", "(x)(x)(x)\\4*", "(x)(x)(x)(x)(x)(x)(x)(x)(x)(x)\\10", "(x)(x)(x)(x)(x)(x)(x)(x)(x)(x)\\11", "(a)\\1", "(a\\1)", "(\\1a)", "(\\2)(\\1)", "(?=a){0,10}a", "(?=a){1,10}a", "(?=a){9,10}a", "(?!a)?a", "\\1(a)", "(?!(a))\\1", "(?!\\1(a\\1)\\1)\\1", "\\1\\2(a(?:\\1(b\\1\\2))\\2)\\1", "[\\0]", "[\\11]", "[\\11a]", "[\\011]", "[\\00011]", "[\\118]", "[\\111]", "[\\1111]", "\\x60", "\\x3z", "\\c", "\\u0034", "\\u003z", "foo[z]*", "\\u{12345}", "\\u{12345}\\u{23456}", "\\u{12345}{3}", "\\u{12345}*", "\\ud808\\udf45*", "[\\ud808\\udf45-\\ud809\\udccc]", "a", "a|b", "a\\n", "a$", "a\\b!", "a\\Bb", "a*?", "a?", "a??", "a{0,1}?", "a{1,2}?", "a+?", "(a)", "(a)\\1", "(\\1a)", "\\1(a)", "a\\s", "a\\S", "a\\D", "a\\w", "a\\W", "a.", "a\\q", "a[a]", "a[^a]", "a[a-z]", "a(?:b)", "a(?=b)", "a(?!b)", "\\x60", "\\u0060", "\\cA", "\\q", "\\1112", "(a)\\1", "(?!a)?a\\1", "(?:(?=a))a\\1", "a{}", "a{,}", "a{", "a{z}", "a{12z}", "a{12,", "a{12,3b", "{}", "{,}", "{", "{z}", "{1z}", "{12,", "{12,3b", "a", "abc", "a[bc]d", "a|bc", "ab|c", "a||bc", "(?:ab)", "(?:ab|cde)", "(?:ab)|cde", "(ab)", "(ab|cde)", "(ab)\\1", "(ab|cde)\\1", "(?:ab)?", "(?:ab)+", "a?", "a+", "a??", "a*?", "a+?", "(?:a?)?", "(?:a+)?", "(?:a?)+", "(?:a*)+", "(?:a+)+", "(?:a?)*", "(?:a*)*", "(?:a+)*", "a{0}", "(?:a+){0,0}", "a*b", "a+b", "a*b|c", "a+b|c", "(?:a{5,1000000}){3,1000000}", "(?:ab){4,7}", "a\\bc", "a\\sc", "a\\Sc", "a(?=b)c", "a(?=bbb|bb)c", "a(?!bbb|bb)c", "\xe2\x81\xa3", "[\xe2\x81\xa3]", "\xed\xb0\x80", "\xed\xa0\x80", "(\xed\xb0\x80)\x01", "((\xed\xa0\x80))\x02", "\xf0\x9f\x92\xa9", "\x01", "\x0f", "[-\xf0\x9f\x92\xa9]+", "[\xf0\x9f\x92\xa9-\xf4\x8f\xbf\xbf]", "(?<=)", "(?<=a)", "(?<!)", "(?<!a)", "(?<a>)", "(?<a>.)", "(?<a>.)\\k<a>", "\\p{Script=Greek}", "\\P{sc=Greek}", "\\p{Script_Extensions=Greek}", "\\P{scx=Greek}", "\\p{General_Category=Decimal_Number}", "\\P{gc=Decimal_Number}", "\\p{gc=Nd}", "\\P{Decimal_Number}", "\\p{Nd}", "\\P{Any}", "\\p{Changes_When_NFKC_Casefolded}", }; static constexpr int preset_pattern_count = arraysize(preset_patterns); static_assert(preset_pattern_count < 0xFF); return std::string(preset_patterns[RandomByte(args) % preset_pattern_count]); } std::string PickPattern(FuzzerArgs* args) { if ((RandomByte(args) & 3) == 0) { return NaiveEscape(GenerateRandomPattern(args), '/'); } else { return PickRandomPresetPattern(args); } } std::string GenerateRandomString(FuzzerArgs* args) { const int kMaxStringLength = 64; return GenerateRandomString(args, RandomByte(args) % kMaxStringLength); } std::string PickSubjectString(FuzzerArgs* args) { if ((RandomByte(args) & 0xF) == 0) { // Sometimes we have a two-byte subject string. return "f\\uD83D\\uDCA9ba\\u2603"; } else { return NaiveEscape(GenerateRandomString(args), '\''); } } std::string PickReplacementForReplace(FuzzerArgs* args) { static const char* candidates[] = { "'X'", "'$1$2$3'", "'$$$&$`$\\'$1'", "() => 'X'", "(arg0, arg1, arg2, arg3, arg4) => arg0 + arg1 + arg2 + arg3 + arg4", "() => 42", }; static const int candidate_count = arraysize(candidates); if ((RandomByte(args) & 1) == 0) { return candidates[RandomByte(args) % candidate_count]; } else { return std::string("'") + NaiveEscape(GenerateRandomString(args), '\'') + std::string("'"); } } std::string PickLimitForSplit(FuzzerArgs* args) { // clang-format off switch (RandomByte(args) & 0x3) { case 0: return "undefined"; case 1: return "'not a number'"; case 2: return std::to_string(Smi::kMaxValue + RandomByte(args)); case 3: return std::to_string(RandomByte(args)); default: UNREACHABLE(); } // clang-format on } std::string GenerateRandomFlags(FuzzerArgs* args) { // TODO(mbid,v8:10765): Find a way to generate the kLinear flag sometimes, // but only for patterns that are supported by the experimental engine. constexpr size_t kFlagCount = JSRegExp::kFlagCount; CHECK_EQ(JSRegExp::kHasIndices, 1 << (kFlagCount - 1)); CHECK_EQ(JSRegExp::kLinear, 1 << (kFlagCount - 2)); CHECK_EQ(JSRegExp::kDotAll, 1 << (kFlagCount - 3)); static_assert((1 << kFlagCount) - 1 <= 0xFF); const size_t flags = RandomByte(args) & ((1 << kFlagCount) - 1); int cursor = 0; char buffer[kFlagCount] = {'\0'}; if (flags & JSRegExp::kGlobal) buffer[cursor++] = 'g'; if (flags & JSRegExp::kIgnoreCase) buffer[cursor++] = 'i'; if (flags & JSRegExp::kMultiline) buffer[cursor++] = 'm'; if (flags & JSRegExp::kSticky) buffer[cursor++] = 'y'; if (flags & JSRegExp::kUnicode) buffer[cursor++] = 'u'; if (flags & JSRegExp::kDotAll) buffer[cursor++] = 's'; if (flags & JSRegExp::kHasIndices) buffer[cursor++] = 'd'; return std::string(buffer, cursor); } std::string GenerateRandomLastIndex(FuzzerArgs* args) { static const char* candidates[] = { "undefined", "-1", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "50", "4294967296", "2147483647", "2147483648", "NaN", "Not a Number", }; static const int candidate_count = arraysize(candidates); return candidates[RandomByte(args) % candidate_count]; } void RunTest(FuzzerArgs* args) { switch (RandomByte(args) % kRegExpBuiltinCount) { #define CASE(name, ...) \ case kRegExpPrototype##name: \ TestRegExpPrototype##name(args); \ break; REGEXP_BUILTINS(CASE) #undef CASE default: UNREACHABLE(); } } std::string GenerateSourceString(FuzzerArgs* args, const std::string& test) { std::string pattern = PickPattern(args); std::string flags = GenerateRandomFlags(args); std::string last_index = GenerateRandomLastIndex(args); std::string subject = PickSubjectString(args); // clang-format off std::stringstream ss; ss << "function test() {\n" << " const re = /" << pattern<< "/" << flags << ";\n" << " re.lastIndex = " << last_index << ";\n" << " const str = '" << subject << "';\n" << " let result = null;\n" << " let exception = null;\n" << " try {\n" << " result = " << test << "\n" << " } catch (e) {\n" << " exception = e;\n" << " }\n" << " return { result: result, re: re, exception: exception };\n" << "}\n" << "%SetForceSlowPath(false);\n" << "test(); // Run once ahead of time to compile the regexp.\n" << "const fast = test();\n" << "%SetForceSlowPath(true);\n" << "const slow = test();\n" << "%SetForceSlowPath(false);\n"; // clang-format on std::string source = ss.str(); if (kVerbose) { fprintf(stderr, "Generated source:\n```\n%s\n```\n", source.c_str()); } return source; } void PrintExceptionMessage(v8::Isolate* isolate, v8::TryCatch* try_catch) { CHECK(try_catch->HasCaught()); static const int kBufferLength = 256; char buffer[kBufferLength + 1]; try_catch->Message()->Get()->WriteOneByte( isolate, reinterpret_cast<uint8_t*>(&buffer[0]), 0, kBufferLength); fprintf(stderr, "%s\n", buffer); } bool ResultsAreIdentical(FuzzerArgs* args) { std::string source = "assertEquals(fast.exception, slow.exception);\n" "assertEquals(fast.result, slow.result);\n" "if (fast.result !== null) {\n" " assertEquals(fast.result.groups, slow.result.groups);\n" " assertEquals(fast.result.indices, slow.result.indices);\n" " if (fast.result.indices !== undefined) {\n" " assertEquals(fast.result.indices.groups,\n" " slow.result.indices.groups);\n" " }\n" "}\n" "assertEquals(fast.re.lastIndex, slow.re.lastIndex);\n"; v8::Local<v8::Value> result; v8::Isolate* isolate = reinterpret_cast<v8::Isolate*>(args->isolate); v8::TryCatch try_catch(isolate); if (!CompileRun(args->context, source.c_str()).ToLocal(&result)) { PrintExceptionMessage(isolate, &try_catch); args->isolate->clear_pending_exception(); return false; } return true; } void CompileRunAndVerify(FuzzerArgs* args, const std::string& source) { v8::Local<v8::Value> result; v8::Isolate* isolate = reinterpret_cast<v8::Isolate*>(args->isolate); v8::TryCatch try_catch(isolate); if (!CompileRun(args->context, source.c_str()).ToLocal(&result)) { args->isolate->clear_pending_exception(); // No need to verify result if an exception was thrown here, since that // implies a syntax error somewhere in the pattern or string. We simply // ignore those. if (kVerbose) { PrintExceptionMessage(isolate, &try_catch); fprintf(stderr, "Failed to run script:\n```\n%s\n```\n", source.c_str()); } return; } if (!ResultsAreIdentical(args)) { uint32_t raw_hash_field = StringHasher::HashSequentialString( args->input_data, static_cast<int>(args->input_length), kRegExpBuiltinsFuzzerHashSeed); FATAL("!ResultAreIdentical(args); RegExpBuiltinsFuzzerHash=%x", raw_hash_field); } } void TestRegExpPrototypeExec(FuzzerArgs* args) { std::string test = "re.exec(str);"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } void TestRegExpPrototypeMatch(FuzzerArgs* args) { std::string test = "re[Symbol.match](str);"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } void TestRegExpPrototypeReplace(FuzzerArgs* args) { std::string replacement = PickReplacementForReplace(args); std::string test = "re[Symbol.replace](str, " + replacement + ");"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } void TestRegExpPrototypeSearch(FuzzerArgs* args) { std::string test = "re[Symbol.search](str);"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } void TestRegExpPrototypeSplit(FuzzerArgs* args) { std::string limit = PickLimitForSplit(args); std::string test = "re[Symbol.split](str, " + limit + ");"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } void TestRegExpPrototypeTest(FuzzerArgs* args) { std::string test = "re.test(str);"; std::string source = GenerateSourceString(args, test); CompileRunAndVerify(args, source); } #undef REGEXP_BUILTINS } // namespace extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) { if (size < 64) return 0; // Need a minimal amount of randomness to do stuff. // Flag definitions. FLAG_allow_natives_syntax = true; // V8 setup. v8_fuzzer::FuzzerSupport* support = v8_fuzzer::FuzzerSupport::Get(); v8::Isolate* isolate = support->GetIsolate(); Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate); v8::Isolate::Scope isolate_scope(isolate); v8::HandleScope handle_scope(isolate); v8::Local<v8::Context> context = support->GetContext(); v8::Context::Scope context_scope(context); v8::TryCatch try_catch(isolate); CHECK(!i_isolate->has_pending_exception()); // And run. FuzzerArgs args(data, size, context, i_isolate); CompileMjsunit(&args); RunTest(&args); CHECK(!i_isolate->has_pending_exception()); return 0; } } // namespace internal } // namespace v8