77 lines · c
1// RUN: %clang_cc1 -Wstrncat-size -verify -fsyntax-only %s2// RUN: %clang_cc1 -DUSE_BUILTINS -Wstrncat-size -verify -fsyntax-only %s3// RUN: %clang_cc1 -Wstrncat-size -fixit -x c %s4// RUN: %clang_cc1 -DUSE_BUILTINS -Wstrncat-size -fixit -x c %s5 6typedef __SIZE_TYPE__ size_t;7size_t strlen (const char *s);8 9#ifdef USE_BUILTINS10# define BUILTIN(f) __builtin_ ## f11#else12# define BUILTIN(f) f13#endif14 15#define strncat BUILTIN(strncat)16char *strncat(char *restrict s1, const char *restrict s2, size_t n);17 18struct {19 char f1[100];20 char f2[100][3];21} s4, **s5;22 23char s1[100];24char s2[200];25int x;26 27void test(char *src) {28 char dest[10];29 30 strncat(dest, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAA", sizeof(dest) - strlen(dest) - 1); // no-warning31 strncat(dest, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAA", sizeof(dest) - 1); // no-warning - the code might assume that dest is empty32 33 strncat(dest, src, sizeof(src)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}34 35 strncat(dest, src, sizeof(src) - 1); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}36 37 strncat(dest, "AAAAAAAAAAAAAAAAAAAAAAAAAAA", sizeof(dest)); // expected-warning{{the value of the size argument in 'strncat' is too large, might lead to a buffer overflow}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}38 39 strncat(dest, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", sizeof(dest) - strlen(dest)); // expected-warning{{the value of the size argument in 'strncat' is too large, might lead to a buffer overflow}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}40 41 strncat((*s5)->f2[x], s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}42 strncat(s1+3, s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-warning {{strncat' size argument is too large; destination buffer has size 97, but size argument is 200}}43 strncat(s4.f1, s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}44}45 46// Don't issue FIXIT for flexible arrays.47struct S {48 int y;49 char x[];50};51 52void flexible_arrays(struct S *s) {53 char str[] = "hi";54 strncat(s->x, str, sizeof(str)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}}55}56 57// Don't issue FIXIT for destinations of size 1.58void size_1(void) {59 char z[1];60 char str[] = "hi";61 62 strncat(z, str, sizeof(z)); // expected-warning{{the value of the size argument to 'strncat' is wrong}}63}64 65// Support VLAs.66void vlas(int size) {67 char z[size];68 char str[] = "hi";69 70 strncat(z, str, sizeof(str)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}}71}72 73// Non-array type gets a different error message.74void f(char* s, char* d) {75 strncat(d, s, sizeof(d)); // expected-warning {{the value of the size argument to 'strncat' is wrong}}76}77