1// Test strict_string_checks option in strncmp function
2// RUN: %clang_asan %s -o %t
3
4// RUN: %env_asan_opts=strict_string_checks=false %run %t a 2>&1
5// RUN: %env_asan_opts=strict_string_checks=true %run %t a 2>&1
6// RUN: not %run %t b 2>&1 | FileCheck %s
7// RUN: not %run %t c 2>&1 | FileCheck %s
8// RUN: not %run %t d 2>&1 | FileCheck %s
9// RUN: not %run %t e 2>&1 | FileCheck %s
10// RUN: not %run %t f 2>&1 | FileCheck %s
11// RUN: not %run %t g 2>&1 | FileCheck %s
12// RUN: %env_asan_opts=strict_string_checks=false %run %t h 2>&1
13// RUN: %env_asan_opts=strict_string_checks=true not %run %t h 2>&1 | FileCheck %s
14// RUN: %env_asan_opts=strict_string_checks=false %run %t i 2>&1
15// RUN: %env_asan_opts=strict_string_checks=true not %run %t i 2>&1 | FileCheck %s
16
17#include <assert.h>
18#include <stdlib.h>
19#include <stdio.h>
20#include <string.h>
21#include <ctype.h>
22
23int main(int argc, char **argv) {
24 assert(argc >= 2);
25 enum { size = 100 };
26 char fill = 'o';
27 char s1[size];
28 char s2[size];
29 memset(s: s1, c: fill, n: size);
30 memset(s: s2, c: fill, n: size);
31
32 switch (argv[1][0]) {
33 case 'a':
34 s1[size - 1] = 'z';
35 s2[size - 1] = 'x';
36 for (int i = 0; i <= size; ++i)
37 assert((strncmp(s1, s2, i) == 0) == (i < size));
38 s1[size - 1] = '\0';
39 s2[size - 1] = '\0';
40 assert(strncmp(s1, s2, 2*size) == 0);
41 break;
42 case 'b':
43 return strncmp(s1: s1-1, s2: s2, n: 1);
44 case 'c':
45 return strncmp(s1: s1, s2: s2-1, n: 1);
46 case 'd':
47 return strncmp(s1: s1+size, s2: s2, n: 1);
48 case 'e':
49 return strncmp(s1: s1, s2: s2+size, n: 1);
50 case 'f':
51 return strncmp(s1: s1+1, s2: s2, n: size);
52 case 'g':
53 return strncmp(s1: s1, s2: s2+1, n: size);
54 case 'h':
55 s1[size - 1] = '\0';
56 assert(strncmp(s1, s2, 2*size) != 0);
57 break;
58 case 'i':
59 s2[size - 1] = '\0';
60 assert(strncmp(s1, s2, 2*size) != 0);
61 break;
62 // CHECK: {{.*}}ERROR: AddressSanitizer: stack-buffer-{{ov|und}}erflow on address
63 }
64 return 0;
65}
66

source code of compiler-rt/test/asan/TestCases/strncmp_strict.c