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