1// RUN: %clangxx_scudo %s -lstdc++ -o %t
2// RUN: %run %t pointers 2>&1
3// RUN: %run %t contents 2>&1
4// RUN: %run %t usablesize 2>&1
5
6// Tests that our reallocation function returns the same pointer when the
7// requested size can fit into the previously allocated chunk. Also tests that
8// a new chunk is returned if the size is greater, and that the contents of the
9// chunk are left unchanged. Finally, checks that realloc copies the usable
10// size of the old chunk to the new one (as opposed to the requested size).
11
12#include <assert.h>
13#include <malloc.h>
14#include <string.h>
15
16#include <vector>
17
18#include <sanitizer/allocator_interface.h>
19
20int main(int argc, char **argv)
21{
22 void *p, *old_p;
23 // Those sizes will exercise both allocators (Primary & Secondary).
24 std::vector<size_t> sizes{1, 16, 1024, 32768, 1 << 16, 1 << 17, 1 << 20};
25
26 assert(argc == 2);
27
28 if (!strcmp(argv[1], "usablesize")) {
29 // This tests a sketchy behavior inherited from poorly written libraries
30 // that have become somewhat standard. When realloc'ing a chunk, the
31 // copied contents should span the usable size of the chunk, not the
32 // requested size.
33 size_t size = 496, usable_size;
34 p = nullptr;
35 // Make sure we get a chunk with a usable size actually larger than size.
36 do {
37 if (p) free(p);
38 size += 16;
39 p = malloc(size);
40 usable_size = __sanitizer_get_allocated_size(p);
41 assert(usable_size >= size);
42 } while (usable_size == size);
43 for (int i = 0; i < usable_size; i++)
44 reinterpret_cast<char *>(p)[i] = 'A';
45 old_p = p;
46 // Make sure we get a different chunk so that the data is actually copied.
47 do {
48 size *= 2;
49 p = realloc(p, size);
50 assert(p);
51 } while (p == old_p);
52 // The contents of the new chunk must match the old one up to usable_size.
53 for (int i = 0; i < usable_size; i++)
54 assert(reinterpret_cast<char *>(p)[i] == 'A');
55 free(p);
56 } else {
57 for (size_t size : sizes) {
58 if (!strcmp(argv[1], "pointers")) {
59 old_p = p = realloc(nullptr, size);
60 assert(p);
61 size = __sanitizer_get_allocated_size(p);
62 // Our realloc implementation will return the same pointer if the size
63 // requested is lower than or equal to the usable size of the associated
64 // chunk.
65 p = realloc(p, size - 1);
66 assert(p == old_p);
67 p = realloc(p, size);
68 assert(p == old_p);
69 // And a new one if the size is greater.
70 p = realloc(p, size + 1);
71 assert(p != old_p);
72 // A size of 0 will free the chunk and return nullptr.
73 p = realloc(p, 0);
74 assert(!p);
75 old_p = nullptr;
76 }
77 if (!strcmp(argv[1], "contents")) {
78 p = realloc(nullptr, size);
79 assert(p);
80 for (int i = 0; i < size; i++)
81 reinterpret_cast<char *>(p)[i] = 'A';
82 p = realloc(p, size + 1);
83 // The contents of the reallocated chunk must match the original one.
84 for (int i = 0; i < size; i++)
85 assert(reinterpret_cast<char *>(p)[i] == 'A');
86 }
87 }
88 }
89 return 0;
90}
91
92// CHECK: ERROR: invalid chunk type when reallocating address
93