src/compiler-rt/test/asan/TestCases/large_allocator_unpoisons_on_free.cc

   1 // Test that LargeAllocator unpoisons memory before releasing it to the OS.
   2 // RUN: %clangxx_asan %s -o %t
   3 // The memory is released only when the deallocated chunk leaves the quarantine,
   4 // otherwise the mmap(p, ...) call overwrites the malloc header.
   5 // RUN: ASAN_OPTIONS=quarantine_size=1 %run %t
   6
   7 #include <assert.h>
   8 #include <string.h>
   9 #include <sys/mman.h>
  10 #include <stdlib.h>
  11
  12 #ifdef __ANDROID__
  13 #include <malloc.h>
  14 void *my_memalign(size_t boundary, size_t size) {
  15   return memalign(boundary, size);
  16 }
  17 #else
  18 void *my_memalign(size_t boundary, size_t size) {
  19   void *p;
  20   posix_memalign(&p, boundary, size);
  21   return p;
  22 }
  23 #endif
  24
  25 int main() {
  26   const int kPageSize = 4096;
  27   void *p = my_memalign(kPageSize, 1024 * 1024);
  28   free(p);
  29
  30   char *q = (char *)mmap(p, kPageSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON | MAP_FIXED, 0, 0);
  31   assert(q == p);
  32
  33   memset(q, 42, kPageSize);
  34
  35   munmap(q, kPageSize);
  36   return 0;
  37 }