| 1 | // RUN: %clangxx_asan -O0 -mllvm -asan-instrument-dynamic-allocas %s -o %t |
|---|---|
| 2 | // RUN: %env_asan_opts=detect_stack_use_after_return=0 %run %t 2>&1 |
| 3 | // |
| 4 | // REQUIRES: stable-runtime |
| 5 | |
| 6 | // This testcase checks that allocas and VLAs inside loop are correctly unpoisoned. |
| 7 | |
| 8 | // MSVC doesn't support VLAs in the first place. |
| 9 | // UNSUPPORTED: msvc |
| 10 | |
| 11 | #include "defines.h" |
| 12 | #include "sanitizer/asan_interface.h" |
| 13 | #include <assert.h> |
| 14 | #include <stdint.h> |
| 15 | #include <stdlib.h> |
| 16 | |
| 17 | // MSVC provides _alloca instead of alloca. |
| 18 | #if defined(_MSC_VER) && !defined(alloca) |
| 19 | # define alloca _alloca |
| 20 | #endif |
| 21 | |
| 22 | #if defined(__sun__) && defined(__svr4__) |
| 23 | #include <alloca.h> |
| 24 | #endif |
| 25 | |
| 26 | void *top, *bot; |
| 27 | |
| 28 | ATTRIBUTE_NOINLINE void foo(int len) { |
| 29 | char x; |
| 30 | top = &x; |
| 31 | volatile char array[len]; |
| 32 | if (len) |
| 33 | array[0] = 0; |
| 34 | assert(!(reinterpret_cast<uintptr_t>(array) & 31L)); |
| 35 | alloca(len); |
| 36 | for (int i = 0; i < 32; ++i) { |
| 37 | volatile char array[i]; |
| 38 | if (i) |
| 39 | array[0] = 0; |
| 40 | bot = alloca(i); |
| 41 | assert(!(reinterpret_cast<uintptr_t>(bot) & 31L)); |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | int main(int argc, char **argv) { |
| 46 | foo(len: 32); |
| 47 | void *q = __asan_region_is_poisoned(beg: bot, size: (char *)top - (char *)bot); |
| 48 | assert(!q); |
| 49 | return 0; |
| 50 | } |
| 51 |