1 /* alloc - Convenience routines for safely allocating memory
2 * Copyright (C) 2007-2009 Josh Coalson
3 * Copyright (C) 2011-2016 Xiph.Org Foundation
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * - Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * - Neither the name of the Xiph.org Foundation nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
28 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
29 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
30 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #ifndef FLAC__SHARE__ALLOC_H
34 #define FLAC__SHARE__ALLOC_H
35
36 #ifdef HAVE_CONFIG_H
37 # include <config.h>
38 #endif
39
40 /* WATCHOUT: for c++ you may have to #define __STDC_LIMIT_MACROS 1 real early
41 * before #including this file, otherwise SIZE_MAX might not be defined
42 */
43
44 #include <limits.h> /* for SIZE_MAX */
45 #if HAVE_STDINT_H
46 #include <stdint.h> /* for SIZE_MAX in case limits.h didn't get it */
47 #endif
48 #include <stdlib.h> /* for size_t, malloc(), etc */
49 #include "share/compat.h"
50
51 #ifndef SIZE_MAX
52 # ifndef SIZE_T_MAX
53 # ifdef _MSC_VER
54 # ifdef _WIN64
55 # define SIZE_T_MAX FLAC__U64L(0xffffffffffffffff)
56 # else
57 # define SIZE_T_MAX 0xffffffff
58 # endif
59 # else
60 # error
61 # endif
62 # endif
63 # define SIZE_MAX SIZE_T_MAX
64 #endif
65
66 /* avoid malloc()ing 0 bytes, see:
67 * https://www.securecoding.cert.org/confluence/display/seccode/MEM04-A.+Do+not+make+assumptions+about+the+result+of+allocating+0+bytes?focusedCommentId=5407003
68 */
safe_malloc_(size_t size)69 static inline void *safe_malloc_(size_t size)
70 {
71 /* malloc(0) is undefined; FLAC src convention is to always allocate */
72 if(!size)
73 size++;
74 return malloc(size);
75 }
76
safe_calloc_(size_t nmemb,size_t size)77 static inline void *safe_calloc_(size_t nmemb, size_t size)
78 {
79 if(!nmemb || !size)
80 return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
81 return calloc(nmemb, size);
82 }
83
84 /*@@@@ there's probably a better way to prevent overflows when allocating untrusted sums but this works for now */
85
safe_malloc_add_2op_(size_t size1,size_t size2)86 static inline void *safe_malloc_add_2op_(size_t size1, size_t size2)
87 {
88 size2 += size1;
89 if(size2 < size1)
90 return 0;
91 return safe_malloc_(size2);
92 }
93
safe_malloc_add_3op_(size_t size1,size_t size2,size_t size3)94 static inline void *safe_malloc_add_3op_(size_t size1, size_t size2, size_t size3)
95 {
96 size2 += size1;
97 if(size2 < size1)
98 return 0;
99 size3 += size2;
100 if(size3 < size2)
101 return 0;
102 return safe_malloc_(size3);
103 }
104
safe_malloc_add_4op_(size_t size1,size_t size2,size_t size3,size_t size4)105 static inline void *safe_malloc_add_4op_(size_t size1, size_t size2, size_t size3, size_t size4)
106 {
107 size2 += size1;
108 if(size2 < size1)
109 return 0;
110 size3 += size2;
111 if(size3 < size2)
112 return 0;
113 size4 += size3;
114 if(size4 < size3)
115 return 0;
116 return safe_malloc_(size4);
117 }
118
119 void *safe_malloc_mul_2op_(size_t size1, size_t size2) ;
120
safe_malloc_mul_3op_(size_t size1,size_t size2,size_t size3)121 static inline void *safe_malloc_mul_3op_(size_t size1, size_t size2, size_t size3)
122 {
123 if(!size1 || !size2 || !size3)
124 return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
125 if(size1 > SIZE_MAX / size2)
126 return 0;
127 size1 *= size2;
128 if(size1 > SIZE_MAX / size3)
129 return 0;
130 return malloc(size1*size3);
131 }
132
133 /* size1*size2 + size3 */
safe_malloc_mul2add_(size_t size1,size_t size2,size_t size3)134 static inline void *safe_malloc_mul2add_(size_t size1, size_t size2, size_t size3)
135 {
136 if(!size1 || !size2)
137 return safe_malloc_(size3);
138 if(size1 > SIZE_MAX / size2)
139 return 0;
140 return safe_malloc_add_2op_(size1*size2, size3);
141 }
142
143 /* size1 * (size2 + size3) */
safe_malloc_muladd2_(size_t size1,size_t size2,size_t size3)144 static inline void *safe_malloc_muladd2_(size_t size1, size_t size2, size_t size3)
145 {
146 if(!size1 || (!size2 && !size3))
147 return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
148 size2 += size3;
149 if(size2 < size3)
150 return 0;
151 if(size1 > SIZE_MAX / size2)
152 return 0;
153 return malloc(size1*size2);
154 }
155
safe_realloc_(void * ptr,size_t size)156 static inline void *safe_realloc_(void *ptr, size_t size)
157 {
158 void *oldptr = ptr;
159 void *newptr = realloc(ptr, size);
160 if(size > 0 && newptr == 0)
161 free(oldptr);
162 return newptr;
163 }
safe_realloc_add_2op_(void * ptr,size_t size1,size_t size2)164 static inline void *safe_realloc_add_2op_(void *ptr, size_t size1, size_t size2)
165 {
166 size2 += size1;
167 if(size2 < size1) {
168 free(ptr);
169 return 0;
170 }
171 return realloc(ptr, size2);
172 }
173
safe_realloc_add_3op_(void * ptr,size_t size1,size_t size2,size_t size3)174 static inline void *safe_realloc_add_3op_(void *ptr, size_t size1, size_t size2, size_t size3)
175 {
176 size2 += size1;
177 if(size2 < size1)
178 return 0;
179 size3 += size2;
180 if(size3 < size2)
181 return 0;
182 return realloc(ptr, size3);
183 }
184
safe_realloc_add_4op_(void * ptr,size_t size1,size_t size2,size_t size3,size_t size4)185 static inline void *safe_realloc_add_4op_(void *ptr, size_t size1, size_t size2, size_t size3, size_t size4)
186 {
187 size2 += size1;
188 if(size2 < size1)
189 return 0;
190 size3 += size2;
191 if(size3 < size2)
192 return 0;
193 size4 += size3;
194 if(size4 < size3)
195 return 0;
196 return realloc(ptr, size4);
197 }
198
safe_realloc_mul_2op_(void * ptr,size_t size1,size_t size2)199 static inline void *safe_realloc_mul_2op_(void *ptr, size_t size1, size_t size2)
200 {
201 if(!size1 || !size2)
202 return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
203 if(size1 > SIZE_MAX / size2)
204 return 0;
205 return safe_realloc_(ptr, size1*size2);
206 }
207
208 /* size1 * (size2 + size3) */
safe_realloc_muladd2_(void * ptr,size_t size1,size_t size2,size_t size3)209 static inline void *safe_realloc_muladd2_(void *ptr, size_t size1, size_t size2, size_t size3)
210 {
211 if(!size1 || (!size2 && !size3))
212 return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
213 size2 += size3;
214 if(size2 < size3)
215 return 0;
216 return safe_realloc_mul_2op_(ptr, size1, size2);
217 }
218
219 #endif
220