alloca_loop_unpoisoning.cpp
954 Bytes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
// RUN: %clangxx_asan -O0 -mllvm -asan-instrument-dynamic-allocas %s -o %t
// RUN: %run %t 2>&1
//
// REQUIRES: stable-runtime
// This testcase checks that allocas and VLAs inside loop are correctly unpoisoned.
#include <assert.h>
#include <stdint.h>
#include <stdlib.h>
#include "sanitizer/asan_interface.h"
// MSVC provides _alloca instead of alloca.
#if defined(_MSC_VER) && !defined(alloca)
# define alloca _alloca
#endif
#if defined(__sun__) && defined(__svr4__)
#include <alloca.h>
#endif
void *top, *bot;
__attribute__((noinline)) void foo(int len) {
char x;
top = &x;
char array[len];
assert(!(reinterpret_cast<uintptr_t>(array) & 31L));
alloca(len);
for (int i = 0; i < 32; ++i) {
char array[i];
bot = alloca(i);
assert(!(reinterpret_cast<uintptr_t>(bot) & 31L));
}
}
int main(int argc, char **argv) {
foo(32);
void *q = __asan_region_is_poisoned(bot, (char *)top - (char *)bot);
assert(!q);
return 0;
}