compiler-rt/test/asan/TestCases/Posix/large_allocator_unpoisons_on_free.cpp

   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: %env_asan_opts=quarantine_size_mb=0 %run %t
   6
   7 #include <assert.h>
   8 #include <string.h>
   9 #include <sys/mman.h>
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12
  13 #ifdef __ANDROID__
  14 #include <malloc.h>
  15 void *my_memalign(size_t boundary, size_t size) {
  16   return memalign(boundary, size);
  17 }
  18 #else
  19 void *my_memalign(size_t boundary, size_t size) {
  20   void *p;
  21   posix_memalign(&p, boundary, size);
  22   return p;
  23 }
  24 #endif
  25
  26 int main() {
  27   const long kPageSize = sysconf(_SC_PAGESIZE);
  28   void *p = my_memalign(kPageSize, 1024 * 1024);
  29   free(p);
  30
  31   char *q = (char *)mmap(p, kPageSize, PROT_READ | PROT_WRITE,
  32                          MAP_PRIVATE | MAP_ANON | MAP_FIXED, -1, 0);
  33   assert(q == p);
  34
  35   memset(q, 42, kPageSize);
  36
  37   munmap(q, kPageSize);
  38   return 0;
  39 }