compiler-rt/test/sanitizer_common/TestCases/malloc_hook.cpp

   1 // RUN: %clangxx -O2 %s -o %t && %run %t 2>&1 | FileCheck %s
   2
   3 // Malloc/free hooks are not supported on Windows.
   4 // XFAIL: target={{.*windows-msvc.*}}
   5
   6 // Must not be implemented, no other reason to install interceptors.
   7 // XFAIL: ubsan
   8
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <sanitizer/allocator_interface.h>
  12
  13 extern "C" {
  14 const volatile void *global_ptr;
  15
  16 #define WRITE(s) write(1, s, sizeof(s))
  17
  18 // Note: avoid calling functions that allocate memory in malloc/free
  19 // to avoid infinite recursion.
  20 void __sanitizer_malloc_hook(const volatile void *ptr, size_t sz) {
  21   if (__sanitizer_get_ownership(ptr) && sz == sizeof(int)) {
  22     WRITE("MallocHook\n");
  23     global_ptr = ptr;
  24   }
  25 }
  26 void __sanitizer_free_hook(const volatile void *ptr) {
  27   if (__sanitizer_get_ownership(ptr) && ptr == global_ptr)
  28     WRITE("FreeHook\n");
  29 }
  30 }  // extern "C"
  31
  32 volatile int *x;
  33
  34 void MallocHook1(const volatile void *ptr, size_t sz) { WRITE("MH1\n"); }
  35 void MallocHook2(const volatile void *ptr, size_t sz) { WRITE("MH2\n"); }
  36 void FreeHook1(const volatile void *ptr) { WRITE("FH1\n"); }
  37 void FreeHook2(const volatile void *ptr) { WRITE("FH2\n"); }
  38 // Call this function with uninitialized arguments to poison
  39 // TLS shadow for function parameters before calling operator
  40 // new and, eventually, user-provided hook.
  41 __attribute__((noinline)) void allocate(int *unused1, int *unused2) {
  42   x = reinterpret_cast<int *>(malloc(sizeof(int)));
  43 }
  44
  45 int main() {
  46   __sanitizer_install_malloc_and_free_hooks(MallocHook1, FreeHook1);
  47   __sanitizer_install_malloc_and_free_hooks(MallocHook2, FreeHook2);
  48   int *undef1, *undef2;
  49   allocate(undef1, undef2);
  50   // CHECK: MallocHook
  51   // CHECK: MH1
  52   // CHECK: MH2
  53   // Check that malloc hook was called with correct argument.
  54   if (global_ptr != (void*)x) {
  55     _exit(1);
  56   }
  57
  58   // Check that realloc invokes hooks
  59   // We realloc to 128 here to avoid potential oversizing by allocators
  60   // making this a no-op.
  61   x = reinterpret_cast<int *>(realloc((int *)x, sizeof(int) * 128));
  62   // CHECK-DAG: FreeHook{{[[:space:]].*}}FH1{{[[:space:]].*}}FH2
  63   // CHECK-DAG: MH1{{[[:space:]].*}}MH2
  64
  65   x[0] = 0;
  66   x[127] = -1;
  67   free((void *)x);
  68   // CHECK: FH1
  69   // CHECK: FH2
  70   return 0;
  71 }