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
17int 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

source code of compiler-rt/test/gwp_asan/realloc.cpp