1 // REQUIRES: gwp_asan
2 // RUN: %clangxx_gwp_asan %s -o %t -DTEST_MALLOC
3 // RUN: %expect_crash %run %t 2>&1 | FileCheck %s --check-prefix CHECK-MALLOC
4 
5 // Check both C++98 and C.
6 // RUN: %clangxx_gwp_asan -std=c++98 %s -o %t -DTEST_FREE
7 // RUN: %expect_crash %run %t 2>&1 | FileCheck %s --check-prefix CHECK-FREE
8 // RUN: cp %s %t.c && %clang_gwp_asan %t.c -o %t -DTEST_FREE
9 // RUN: %expect_crash %run %t 2>&1 | FileCheck %s --check-prefix CHECK-FREE
10 
11 // Ensure GWP-ASan stub implementation of realloc() in Scudo works to-spec. In
12 // particular, the behaviour regarding realloc of size zero is interesting, as
13 // it's defined as free().
14 
15 #include <stdlib.h>
16 
main()17 int main() {
18 #if defined(TEST_MALLOC)
19   // realloc(nullptr, size) is equivalent to malloc(size).
20   char *Ptr = reinterpret_cast<char *>(realloc(nullptr, 1));
21   *Ptr = 0;
22   // Trigger an INVALID_FREE to the right.
23   free(Ptr + 1);
24 
25   // CHECK-MALLOC: GWP-ASan detected a memory error
26   // CHECK-MALLOC: Invalid (Wild) Free at 0x{{[a-f0-9]+}} (1 byte to the right
27   // CHECK-MALLOC-SAME: of a 1-byte allocation
28 #elif defined(TEST_FREE)
29   char *Ptr = (char *) malloc(1);
30   // realloc(ptr, 0) is equivalent to free(ptr) and must return nullptr. Note
31   // that this is only the specification in C++98 and C.
32   if (realloc(Ptr, 0) != NULL) {
33 
34   }
35   // Trigger a USE_AFTER_FREE.
36   *Ptr = 0;
37 
38   // CHECK-FREE: GWP-ASan detected a memory error
39   // CHECK-FREE: Use After Free at 0x{{[a-f0-9]+}} (0 bytes into a 1-byte
40   // CHECK-FREE-SAME: allocation
41 #endif
42 
43   return 0;
44 }
45