1/* Test for reallocarray.
2 Copyright (C) 2017-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <malloc.h>
21#include <string.h>
22#include <support/check.h>
23#include <libc-diag.h>
24
25static void *
26reallocarray_nowarn (void *ptr, size_t nmemb, size_t size)
27{
28#if __GNUC_PREREQ (7, 0)
29 /* GCC 7 warns about too-large allocations; here we want to test
30 that they fail. */
31 DIAG_IGNORE_NEEDS_COMMENT (7, "-Walloc-size-larger-than=");
32#endif
33 void *ret = reallocarray (ptr: ptr, nmemb: nmemb, size: size);
34#if __GNUC_PREREQ (7, 0)
35 DIAG_POP_NEEDS_COMMENT;
36#endif
37 return ret;
38}
39
40
41static int
42do_test (void)
43{
44 void *ptr = NULL;
45 void *ptr2 = NULL;
46 unsigned char *c;
47 size_t i;
48 int ok;
49 const size_t max = ~(size_t)0;
50 size_t a, b;
51
52 /* Test overflow detection. */
53 errno = 0;
54 ptr = reallocarray_nowarn (NULL, nmemb: max, size: 2);
55 TEST_VERIFY (!ptr);
56 TEST_VERIFY (errno == ENOMEM);
57
58 errno = 0;
59 ptr = reallocarray_nowarn (NULL, nmemb: 2, size: max);
60 TEST_VERIFY (!ptr);
61 TEST_VERIFY (errno == ENOMEM);
62
63 a = 65537;
64 b = max/65537 + 1;
65 errno = 0;
66 ptr = reallocarray_nowarn (NULL, nmemb: a, size: b);
67 TEST_VERIFY (!ptr);
68 TEST_VERIFY (errno == ENOMEM);
69
70 errno = 0;
71 ptr = reallocarray_nowarn (NULL, nmemb: b, size: a);
72 TEST_VERIFY (!ptr);
73 TEST_VERIFY (errno == ENOMEM);
74
75 /* Test realloc-like behavior. */
76 /* Allocate memory like malloc. */
77 ptr = reallocarray (NULL, nmemb: 10, size: 2);
78 TEST_VERIFY_EXIT (ptr);
79 TEST_VERIFY_EXIT (malloc_usable_size (ptr) >= 10*2);
80
81 memset (ptr, 0xAF, 10*2);
82
83 /* Enlarge buffer. */
84 ptr2 = reallocarray (ptr: ptr, nmemb: 20, size: 2);
85 TEST_VERIFY (ptr2);
86 if (ptr2)
87 ptr = ptr2;
88 TEST_VERIFY (malloc_usable_size (ptr) >= 20*2);
89
90 c = ptr;
91 ok = 1;
92 for (i = 0; i < 10*2; ++i)
93 {
94 if (c[i] != 0xAF)
95 ok = 0;
96 }
97 TEST_VERIFY (ok);
98
99 /* Decrease buffer size. */
100 ptr2 = reallocarray (ptr: ptr, nmemb: 5, size: 3);
101 TEST_VERIFY (ptr2);
102 if (ptr2)
103 ptr = ptr2;
104 TEST_VERIFY_EXIT (malloc_usable_size (ptr) >= 5*3);
105
106 c = ptr;
107 ok = 1;
108 for (i = 0; i < 5*3; ++i)
109 {
110 if (c[i] != 0xAF)
111 ok = 0;
112 }
113 TEST_VERIFY (ok);
114
115 /* Overflow should leave buffer untouched. */
116 errno = 0;
117 ptr2 = reallocarray_nowarn (ptr, nmemb: 2, size: ~(size_t)0);
118 TEST_VERIFY (!ptr2);
119 TEST_VERIFY (errno == ENOMEM);
120
121 c = ptr;
122 ok = 1;
123 for (i = 0; i < 5*3; ++i)
124 {
125 if (c[i] != 0xAF)
126 ok = 0;
127 }
128 TEST_VERIFY (ok);
129
130 free (ptr: ptr);
131
132 return 0;
133}
134
135#include <support/test-driver.c>
136

source code of glibc/malloc/tst-reallocarray.c