Coverage Report

Created: 2026-06-30 06:15

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/libpng/contrib/oss-fuzz/nalloc.h
Line
Count
Source
1
/*
2
 MIT License
3
4
 Copyright (c) 2025 Catena cyber
5
6
 Permission is hereby granted, free of charge, to any person obtaining a copy
7
 of this software and associated documentation files (the "Software"), to deal
8
 in the Software without restriction, including without limitation the rights
9
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10
 copies of the Software, and to permit persons to whom the Software is
11
 furnished to do so, subject to the following conditions:
12
13
 The above copyright notice and this permission notice shall be included in all
14
 copies or substantial portions of the Software.
15
16
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22
 SOFTWARE.
23
*/
24
25
#ifndef NALLOC_H_
26
#define NALLOC_H_
27
28
#define FUZZER_ENABLE_NALLOC 1
29
#if defined(__has_feature)
30
#if __has_feature(memory_sanitizer)
31
#undef FUZZER_ENABLE_NALLOC
32
#endif
33
#endif
34
35
#if !defined(FUZZER_ENABLE_NALLOC)
36
#define nalloc_init(x)
37
#define nalloc_restrict_file_prefix(x)
38
#define nalloc_start(x, y)
39
#define nalloc_end()
40
#else
41
42
#if defined(__clang__) && defined(__has_feature)
43
#if __has_feature(address_sanitizer)
44
#define NALLOC_ASAN 1
45
#endif
46
#endif
47
48
#include <errno.h>
49
#include <stdbool.h>
50
#include <stdint.h>
51
#include <stdio.h>
52
#include <stdlib.h>
53
#include <string.h>
54
55
#ifdef __cplusplus
56
extern "C" {
57
#endif
58
59
static const uint32_t nalloc_crc32_table[] = {
60
  0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
61
  0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
62
  0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7,
63
  0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
64
  0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3,
65
  0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
66
  0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef,
67
  0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
68
  0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb,
69
  0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
70
  0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
71
  0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
72
  0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4,
73
  0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
74
  0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08,
75
  0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
76
  0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc,
77
  0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
78
  0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050,
79
  0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
80
  0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
81
  0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
82
  0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1,
83
  0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
84
  0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5,
85
  0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
86
  0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9,
87
  0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
88
  0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd,
89
  0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
90
  0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
91
  0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
92
  0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2,
93
  0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
94
  0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e,
95
  0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
96
  0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a,
97
  0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
98
  0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676,
99
  0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
100
  0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
101
  0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
102
  0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
103
};
104
105
// Nallocfuzz data to take a decision
106
uint32_t nalloc_random_state = 0;
107
__thread unsigned int nalloc_running = 0;
108
bool nalloc_initialized = false;
109
uint32_t nalloc_runs = 0;
110
111
// Nalloc fuzz parameters
112
uint32_t nalloc_bitmask = 0xFF;
113
bool nalloc_random_bitmask = true;
114
uint32_t nalloc_magic = 0x294cee63;
115
bool nalloc_verbose = false;
116
117
#ifdef NALLOC_ASAN
118
extern void __sanitizer_print_stack_trace(void);
119
#endif
120
121
// Generic init, using env variables to get parameters
122
7.97k
void nalloc_init(const char *prog) {
123
7.97k
  if (nalloc_initialized) {
124
7.97k
    return;
125
7.97k
  }
126
1
  nalloc_initialized = true;
127
1
  char *bitmask = getenv("NALLOC_FREQ");
128
1
  if (bitmask) {
129
0
    int shift = atoi(bitmask);
130
0
    if (shift > 0 && shift < 31) {
131
0
      nalloc_bitmask = 1 << shift;
132
0
      nalloc_random_bitmask = false;
133
0
    } else if (shift == 0) {
134
0
      nalloc_random_bitmask = false;
135
0
      nalloc_bitmask = 0;
136
0
    }
137
1
  } else if (prog == NULL || strstr(prog, "nalloc") == NULL) {
138
1
    nalloc_random_bitmask = false;
139
1
    nalloc_bitmask = 0;
140
1
    return;
141
1
  }
142
143
0
  char *magic = getenv("NALLOC_MAGIC");
144
0
  if (magic) {
145
0
    nalloc_magic = (uint32_t)strtol(magic, NULL, 0);
146
0
  }
147
148
0
  char *verbose = getenv("NALLOC_VERBOSE");
149
0
  if (verbose) {
150
0
    nalloc_verbose = true;
151
0
  }
152
0
}
153
154
// add one byte to the CRC
155
0
static inline void nalloc_random_update(uint8_t b) {
156
0
  nalloc_random_state =
157
0
      ((uint32_t)((uint32_t)nalloc_random_state << 8)) ^
158
0
      nalloc_crc32_table[((nalloc_random_state >> 24) ^ b) & 0xFF];
159
0
}
160
161
// Start the failure injections, using a buffer as seed
162
7.90k
static int nalloc_start(const uint8_t *data, size_t size) {
163
7.90k
  if (nalloc_random_bitmask) {
164
0
    if (nalloc_random_state & 0x10) {
165
0
      nalloc_bitmask = 0xFFFFFFFF;
166
0
    } else {
167
0
      nalloc_bitmask = 1 << (5 + (nalloc_random_state & 0xF));
168
0
    }
169
7.90k
  } else if (nalloc_bitmask == 0) {
170
    // nalloc disabled
171
7.90k
    return 0;
172
7.90k
  }
173
0
  nalloc_random_state = 0;
174
0
  for (size_t i = 0; i < size; i++) {
175
0
    nalloc_random_update(data[i]);
176
0
  }
177
0
  if (__sync_fetch_and_add(&nalloc_running, 1)) {
178
0
    __sync_fetch_and_sub(&nalloc_running, 1);
179
0
    return 0;
180
0
  }
181
0
  nalloc_runs++;
182
0
  return 1;
183
0
}
184
185
// Stop the failure injections
186
7.90k
static void nalloc_end() { __sync_fetch_and_sub(&nalloc_running, 1); }
187
188
0
static bool nalloc_backtrace_exclude(size_t size, const char *op) {
189
0
  if (nalloc_verbose) {
190
0
    fprintf(stderr, "failed %s(%zu) \n", op, size);
191
#ifdef NALLOC_ASAN
192
    __sanitizer_print_stack_trace();
193
#endif
194
0
  }
195
196
0
  return false;
197
0
}
198
199
//
200
311k
static bool nalloc_fail(size_t size, const char *op) {
201
  // do not fail before thread init
202
311k
  if (nalloc_runs == 0) {
203
311k
    return false;
204
311k
  }
205
0
  if (__sync_fetch_and_add(&nalloc_running, 1) != 1) {
206
    // do not fail allocations outside of fuzzer input
207
    // and do not fail inside of this function
208
0
    __sync_fetch_and_sub(&nalloc_running, 1);
209
0
    return false;
210
0
  }
211
0
  nalloc_random_update((uint8_t)size);
212
0
  if (size >= 0x100) {
213
0
    nalloc_random_update((uint8_t)(size >> 8));
214
0
    if (size >= 0x10000) {
215
0
      nalloc_random_update((uint8_t)(size >> 16));
216
      // bigger may already fail or oom
217
0
    }
218
0
  }
219
0
  if (((nalloc_random_state ^ nalloc_magic) & nalloc_bitmask) == 0) {
220
0
    if (nalloc_backtrace_exclude(size, op)) {
221
0
      __sync_fetch_and_sub(&nalloc_running, 1);
222
0
      return false;
223
0
    }
224
0
    __sync_fetch_and_sub(&nalloc_running, 1);
225
0
    return true;
226
0
  }
227
0
  __sync_fetch_and_sub(&nalloc_running, 1);
228
0
  return false;
229
0
}
230
231
// ASAN interceptor for libc routines
232
#ifdef NALLOC_ASAN
233
extern void *__interceptor_malloc(size_t);
234
extern void *__interceptor_calloc(size_t, size_t);
235
extern void *__interceptor_realloc(void *, size_t);
236
extern void *__interceptor_reallocarray(void *, size_t, size_t);
237
238
extern ssize_t __interceptor_read(int, void *, size_t);
239
extern ssize_t __interceptor_write(int, const void *, size_t);
240
extern ssize_t __interceptor_recv(int, void *, size_t, int);
241
extern ssize_t __interceptor_send(int, const void *, size_t, int);
242
243
#define nalloc_malloc(s) __interceptor_malloc(s)
244
#define nalloc_calloc(s, n) __interceptor_calloc(s, n)
245
#define nalloc_realloc(p, s) __interceptor_realloc(p, s)
246
#define nalloc_reallocarray(p, s, n) __interceptor_reallocarray(p, s, n)
247
248
#define nalloc_read(f, b, s) __interceptor_read(f, b, s)
249
#define nalloc_write(f, b, s) __interceptor_write(f, b, s)
250
#define nalloc_recv(f, b, s, x) __interceptor_recv(f, b, s, x)
251
#define nalloc_send(f, b, s, x) __interceptor_send(f, b, s, x)
252
253
#else
254
extern void *__libc_malloc(size_t);
255
extern void *__libc_calloc(size_t, size_t);
256
extern void *__libc_realloc(void *, size_t);
257
extern void *__libc_reallocarray(void *, size_t, size_t);
258
259
extern ssize_t __read(int, void *, size_t);
260
extern ssize_t __write(int, const void *, size_t);
261
extern ssize_t __recv(int, void *, size_t, int);
262
extern ssize_t __send(int, const void *, size_t, int);
263
264
311k
#define nalloc_malloc(s) __libc_malloc(s)
265
8
#define nalloc_calloc(s, n) __libc_calloc(s, n)
266
3
#define nalloc_realloc(p, s) __libc_realloc(p, s)
267
0
#define nalloc_reallocarray(p, s, n) __libc_reallocarray(p, s, n)
268
269
0
#define nalloc_read(f, b, s) __read(f, b, s)
270
0
#define nalloc_write(f, b, s) __write(f, b, s)
271
0
#define nalloc_recv(f, b, s, x) __recv(f, b, s, x)
272
0
#define nalloc_send(f, b, s, x) __send(f, b, s, x)
273
#endif
274
275
// nalloc standard function overwrites with pseudo-random failures
276
0
ssize_t read(int fd, void *buf, size_t count) {
277
0
  if (nalloc_fail(count, "read")) {
278
0
    errno = EIO;
279
0
    return -1;
280
0
  }
281
0
  return nalloc_read(fd, buf, count);
282
0
}
283
284
0
ssize_t write(int fd, const void *buf, size_t count) {
285
0
  if (nalloc_fail(count, "write")) {
286
0
    errno = EIO;
287
0
    return -1;
288
0
  }
289
0
  return nalloc_write(fd, buf, count);
290
0
}
291
292
0
ssize_t recv(int fd, void *buf, size_t count, int flags) {
293
0
  if (nalloc_fail(count, "recv")) {
294
0
    errno = EIO;
295
0
    return -1;
296
0
  }
297
0
  return nalloc_recv(fd, buf, count, flags);
298
0
}
299
300
0
ssize_t send(int fd, const void *buf, size_t count, int flags) {
301
0
  if (nalloc_fail(count, "send")) {
302
0
    errno = EIO;
303
0
    return -1;
304
0
  }
305
0
  return nalloc_send(fd, buf, count, flags);
306
0
}
307
308
8
void *calloc(size_t nmemb, size_t size) {
309
8
  if (nalloc_fail(size, "calloc")) {
310
0
    errno = ENOMEM;
311
0
    return NULL;
312
0
  }
313
8
  return nalloc_calloc(nmemb, size);
314
8
}
315
316
311k
void *malloc(size_t size) {
317
311k
  if (nalloc_fail(size, "malloc")) {
318
0
    errno = ENOMEM;
319
0
    return NULL;
320
0
  }
321
311k
  return nalloc_malloc(size);
322
311k
}
323
324
3
void *realloc(void *ptr, size_t size) {
325
3
  if (nalloc_fail(size, "realloc")) {
326
0
    errno = ENOMEM;
327
0
    return NULL;
328
0
  }
329
3
  return nalloc_realloc(ptr, size);
330
3
}
331
332
0
void *reallocarray(void *ptr, size_t nmemb, size_t size) {
333
0
  if (nalloc_fail(size, "reallocarray")) {
334
0
    errno = ENOMEM;
335
0
    return NULL;
336
0
  }
337
0
  return nalloc_reallocarray(ptr, nmemb, size);
338
0
}
339
340
#ifdef __cplusplus
341
}  // extern "C" {
342
#endif
343
344
#endif // FUZZER_ENABLE_NALLOC
345
#endif  // NALLOC_H_