1 // Copyright 2021 Code Intelligence GmbH
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include <limits>
16 #include <string>
17 #include <nativehelper/JNIHelp.h>
18 #include <jni.h>
19 #include <stdio.h>
20 #include "example_jni.h"
21
22 // simple function containing a crash that requires coverage and string compare
23 // instrumentation for the fuzzer to find
parseInternal(const std::string & input)24 __attribute__((optnone)) void parseInternal(const std::string &input) {
25 constexpr int bar = std::numeric_limits<int>::max() - 5;
26 // Crashes with UBSan.
27 if (bar + input[0] == 300) {
28 return;
29 }
30 if (input[0] == 'a' && input[1] == 'b' && input[5] == 'c') {
31 if (input.find("intentional_crash_to_test_jni_fuzzing") != std::string::npos) {
32 // Crashes with ASan.
33 [[maybe_unused]] char foo = input[input.size() + 2];
34 }
35 }
36 }
37
Java_ExampleJavaJniFuzzer_parse(JNIEnv * env,jobject o,jstring bytes)38 JNIEXPORT jboolean JNICALL Java_ExampleJavaJniFuzzer_parse(
39 JNIEnv *env, jobject o, jstring bytes) {
40 const char *input(env->GetStringUTFChars(bytes, nullptr));
41 parseInternal(input);
42 env->ReleaseStringUTFChars(bytes, input);
43 return false;
44 }
45