lib/asan/lit_tests/TestCases/Linux/overflow-in-qsort.cc

   1 // RUN: %clangxx_asan -O2 %s -o %t
   2 // RUN: ASAN_OPTIONS=fast_unwind_on_fatal=1 not %t 2>&1 | FileCheck %s --check-prefix=CHECK-FAST
   3 // RUN: ASAN_OPTIONS=fast_unwind_on_fatal=0 not %t 2>&1 | FileCheck %s --check-prefix=CHECK-SLOW
   4
   5 // Test how well we unwind in presence of qsort in the stack
   6 // (i.e. if we can unwind through a function compiled w/o frame pointers).
   7 // https://code.google.com/p/address-sanitizer/issues/detail?id=137
   8
   9 // Fast unwinder is only avaliable on x86_64 and i386.
  10 // REQUIRES: x86_64-supported-target
  11
  12 #include <stdlib.h>
  13 #include <stdio.h>
  14
  15 int global_array[10];
  16 volatile int one = 1;
  17
  18 extern "C" {
  19 int QsortCallback(const void *a, const void *b) {
  20   char *x = (char*)a;
  21   char *y = (char*)b;
  22   printf("Calling QsortCallback\n");
  23   global_array[one * 10] = 0;  // BOOM
  24   return (int)*x - (int)*y;
  25 }
  26
  27 __attribute__((noinline))
  28 void MyQsort(char *a, size_t size) {
  29   printf("Calling qsort\n");
  30   qsort(a, size, sizeof(char), QsortCallback);
  31   printf("Done\n");  // Avoid tail call.
  32 }
  33 }  // extern "C"
  34
  35 int main() {
  36   char a[2] = {1, 2};
  37   MyQsort(a, 2);
  38 }
  39
  40 // Fast unwind: can not unwind through qsort.
  41
  42 // CHECK-FAST: ERROR: AddressSanitizer: global-buffer-overflow
  43 // CHECK-FAST: #0{{.*}} in QsortCallback
  44 // CHECK-FAST-NOT: MyQsort
  45 // CHECK-FAST: is located 0 bytes to the right of global variable 'global_array
  46
  47 // CHECK-SLOW: ERROR: AddressSanitizer: global-buffer-overflow
  48 // CHECK-SLOW: #0{{.*}} in QsortCallback
  49 // CHECK-SLOW: #{{.*}} in MyQsort
  50 // CHECK-SLOW: #{{.*}} in main
  51 // CHECK-SLOW: is located 0 bytes to the right of global variable 'global_array