1 // This file is distributed under the University of Illinois Open Source
2 // License. See LICENSE.TXT for details.
3
4 // Simple test for a fuzzer.
5 // Try to find the target using the indirect caller-callee pairs.
6 #include <cstdint>
7 #include <cstdlib>
8 #include <cstddef>
9 #include <cstring>
10 #include <iostream>
11
12 typedef void (*F)();
13 static F t[256];
14
f34()15 void f34() {
16 std::cerr << "BINGO\n";
17 exit(1);
18 }
f23()19 void f23() { t[(unsigned)'d'] = f34;}
f12()20 void f12() { t[(unsigned)'c'] = f23;}
f01()21 void f01() { t[(unsigned)'b'] = f12;}
f00()22 void f00() {}
23
24 static F t0[256] = {
25 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
26 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
27 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
28 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
29 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
30 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
31 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
32 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
33 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
34 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
35 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
36 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
37 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
38 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
39 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
40 f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00, f00,
41 };
42
LLVMFuzzerTestOneInput(const uint8_t * Data,size_t Size)43 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
44 if (Size < 4) return 0;
45 // Spoof the counters.
46 for (int i = 0; i < 200; i++) {
47 f23();
48 f12();
49 f01();
50 }
51 memcpy(t, t0, sizeof(t));
52 t[(unsigned)'a'] = f01;
53 t[Data[0]]();
54 t[Data[1]]();
55 t[Data[2]]();
56 t[Data[3]]();
57 return 0;
58 }
59
60