Commit | Line | Data |
---|---|---|
aac6c53a MW |
1 | Copied from Debian. |
2 | ||
3 | From: Kurt Roeckx <kurt@roeckx.be> | |
4 | Date: Sun, 28 Jan 2018 19:26:36 +0100 | |
5 | Subject: Check the size before reading with mad_bit_read | |
6 | ||
7 | There are various cases where it attemps to read past the end of the buffer | |
8 | using mad_bit_read(). Most functions didn't even know the size of the buffer | |
9 | they were reading from. | |
10 | ||
11 | Index: libmad-0.15.1b/bit.c | |
12 | =================================================================== | |
13 | --- libmad-0.15.1b.orig/bit.c | |
14 | +++ libmad-0.15.1b/bit.c | |
15 | @@ -138,6 +138,9 @@ unsigned long mad_bit_read(struct mad_bi | |
16 | { | |
17 | register unsigned long value; | |
18 | ||
19 | + if (len == 0) | |
20 | + return 0; | |
21 | + | |
22 | if (bitptr->left == CHAR_BIT) | |
23 | bitptr->cache = *bitptr->byte; | |
24 | ||
25 | Index: libmad-0.15.1b/frame.c | |
26 | =================================================================== | |
27 | --- libmad-0.15.1b.orig/frame.c | |
28 | +++ libmad-0.15.1b/frame.c | |
29 | @@ -120,11 +120,18 @@ static | |
30 | int decode_header(struct mad_header *header, struct mad_stream *stream) | |
31 | { | |
32 | unsigned int index; | |
33 | + struct mad_bitptr bufend_ptr; | |
34 | ||
35 | header->flags = 0; | |
36 | header->private_bits = 0; | |
37 | ||
38 | + mad_bit_init(&bufend_ptr, stream->bufend); | |
39 | + | |
40 | /* header() */ | |
41 | + if (mad_bit_length(&stream->ptr, &bufend_ptr) < 32) { | |
42 | + stream->error = MAD_ERROR_BUFLEN; | |
43 | + return -1; | |
44 | + } | |
45 | ||
46 | /* syncword */ | |
47 | mad_bit_skip(&stream->ptr, 11); | |
48 | @@ -225,8 +232,13 @@ int decode_header(struct mad_header *hea | |
49 | /* error_check() */ | |
50 | ||
51 | /* crc_check */ | |
52 | - if (header->flags & MAD_FLAG_PROTECTION) | |
53 | + if (header->flags & MAD_FLAG_PROTECTION) { | |
54 | + if (mad_bit_length(&stream->ptr, &bufend_ptr) < 16) { | |
55 | + stream->error = MAD_ERROR_BUFLEN; | |
56 | + return -1; | |
57 | + } | |
58 | header->crc_target = mad_bit_read(&stream->ptr, 16); | |
59 | + } | |
60 | ||
61 | return 0; | |
62 | } | |
63 | @@ -338,7 +350,7 @@ int mad_header_decode(struct mad_header | |
64 | stream->error = MAD_ERROR_BUFLEN; | |
65 | goto fail; | |
66 | } | |
67 | - else if (!(ptr[0] == 0xff && (ptr[1] & 0xe0) == 0xe0)) { | |
68 | + else if ((end - ptr >= 2) && !(ptr[0] == 0xff && (ptr[1] & 0xe0) == 0xe0)) { | |
69 | /* mark point where frame sync word was expected */ | |
70 | stream->this_frame = ptr; | |
71 | stream->next_frame = ptr + 1; | |
72 | @@ -361,6 +373,8 @@ int mad_header_decode(struct mad_header | |
73 | ptr = mad_bit_nextbyte(&stream->ptr); | |
74 | } | |
75 | ||
76 | + stream->error = MAD_ERROR_NONE; | |
77 | + | |
78 | /* begin processing */ | |
79 | stream->this_frame = ptr; | |
80 | stream->next_frame = ptr + 1; /* possibly bogus sync word */ | |
81 | @@ -413,7 +427,7 @@ int mad_header_decode(struct mad_header | |
82 | /* check that a valid frame header follows this frame */ | |
83 | ||
84 | ptr = stream->next_frame; | |
85 | - if (!(ptr[0] == 0xff && (ptr[1] & 0xe0) == 0xe0)) { | |
86 | + if ((end - ptr >= 2) && !(ptr[0] == 0xff && (ptr[1] & 0xe0) == 0xe0)) { | |
87 | ptr = stream->next_frame = stream->this_frame + 1; | |
88 | goto sync; | |
89 | } | |
90 | Index: libmad-0.15.1b/layer12.c | |
91 | =================================================================== | |
92 | --- libmad-0.15.1b.orig/layer12.c | |
93 | +++ libmad-0.15.1b/layer12.c | |
94 | @@ -72,10 +72,18 @@ mad_fixed_t const linear_table[14] = { | |
95 | * DESCRIPTION: decode one requantized Layer I sample from a bitstream | |
96 | */ | |
97 | static | |
98 | -mad_fixed_t I_sample(struct mad_bitptr *ptr, unsigned int nb) | |
99 | +mad_fixed_t I_sample(struct mad_bitptr *ptr, unsigned int nb, struct mad_stream *stream) | |
100 | { | |
101 | mad_fixed_t sample; | |
102 | + struct mad_bitptr frameend_ptr; | |
103 | ||
104 | + mad_bit_init(&frameend_ptr, stream->next_frame); | |
105 | + | |
106 | + if (mad_bit_length(ptr, &frameend_ptr) < nb) { | |
107 | + stream->error = MAD_ERROR_LOSTSYNC; | |
108 | + stream->sync = 0; | |
109 | + return 0; | |
110 | + } | |
111 | sample = mad_bit_read(ptr, nb); | |
112 | ||
113 | /* invert most significant bit, extend sign, then scale to fixed format */ | |
114 | @@ -106,6 +114,10 @@ int mad_layer_I(struct mad_stream *strea | |
115 | struct mad_header *header = &frame->header; | |
116 | unsigned int nch, bound, ch, s, sb, nb; | |
117 | unsigned char allocation[2][32], scalefactor[2][32]; | |
118 | + struct mad_bitptr bufend_ptr, frameend_ptr; | |
119 | + | |
120 | + mad_bit_init(&bufend_ptr, stream->bufend); | |
121 | + mad_bit_init(&frameend_ptr, stream->next_frame); | |
122 | ||
123 | nch = MAD_NCHANNELS(header); | |
124 | ||
125 | @@ -118,6 +130,11 @@ int mad_layer_I(struct mad_stream *strea | |
126 | /* check CRC word */ | |
127 | ||
128 | if (header->flags & MAD_FLAG_PROTECTION) { | |
129 | + if (mad_bit_length(&stream->ptr, &bufend_ptr) | |
130 | + < 4 * (bound * nch + (32 - bound))) { | |
131 | + stream->error = MAD_ERROR_BADCRC; | |
132 | + return -1; | |
133 | + } | |
134 | header->crc_check = | |
135 | mad_bit_crc(stream->ptr, 4 * (bound * nch + (32 - bound)), | |
136 | header->crc_check); | |
137 | @@ -133,6 +150,11 @@ int mad_layer_I(struct mad_stream *strea | |
138 | ||
139 | for (sb = 0; sb < bound; ++sb) { | |
140 | for (ch = 0; ch < nch; ++ch) { | |
141 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 4) { | |
142 | + stream->error = MAD_ERROR_LOSTSYNC; | |
143 | + stream->sync = 0; | |
144 | + return -1; | |
145 | + } | |
146 | nb = mad_bit_read(&stream->ptr, 4); | |
147 | ||
148 | if (nb == 15) { | |
149 | @@ -145,6 +167,11 @@ int mad_layer_I(struct mad_stream *strea | |
150 | } | |
151 | ||
152 | for (sb = bound; sb < 32; ++sb) { | |
153 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 4) { | |
154 | + stream->error = MAD_ERROR_LOSTSYNC; | |
155 | + stream->sync = 0; | |
156 | + return -1; | |
157 | + } | |
158 | nb = mad_bit_read(&stream->ptr, 4); | |
159 | ||
160 | if (nb == 15) { | |
161 | @@ -161,6 +188,11 @@ int mad_layer_I(struct mad_stream *strea | |
162 | for (sb = 0; sb < 32; ++sb) { | |
163 | for (ch = 0; ch < nch; ++ch) { | |
164 | if (allocation[ch][sb]) { | |
165 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 6) { | |
166 | + stream->error = MAD_ERROR_LOSTSYNC; | |
167 | + stream->sync = 0; | |
168 | + return -1; | |
169 | + } | |
170 | scalefactor[ch][sb] = mad_bit_read(&stream->ptr, 6); | |
171 | ||
172 | # if defined(OPT_STRICT) | |
173 | @@ -185,8 +217,10 @@ int mad_layer_I(struct mad_stream *strea | |
174 | for (ch = 0; ch < nch; ++ch) { | |
175 | nb = allocation[ch][sb]; | |
176 | frame->sbsample[ch][s][sb] = nb ? | |
177 | - mad_f_mul(I_sample(&stream->ptr, nb), | |
178 | + mad_f_mul(I_sample(&stream->ptr, nb, stream), | |
179 | sf_table[scalefactor[ch][sb]]) : 0; | |
180 | + if (stream->error != 0) | |
181 | + return -1; | |
182 | } | |
183 | } | |
184 | ||
185 | @@ -194,7 +228,14 @@ int mad_layer_I(struct mad_stream *strea | |
186 | if ((nb = allocation[0][sb])) { | |
187 | mad_fixed_t sample; | |
188 | ||
189 | - sample = I_sample(&stream->ptr, nb); | |
190 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < nb) { | |
191 | + stream->error = MAD_ERROR_LOSTSYNC; | |
192 | + stream->sync = 0; | |
193 | + return -1; | |
194 | + } | |
195 | + sample = I_sample(&stream->ptr, nb, stream); | |
196 | + if (stream->error != 0) | |
197 | + return -1; | |
198 | ||
199 | for (ch = 0; ch < nch; ++ch) { | |
200 | frame->sbsample[ch][s][sb] = | |
201 | @@ -280,13 +321,21 @@ struct quantclass { | |
202 | static | |
203 | void II_samples(struct mad_bitptr *ptr, | |
204 | struct quantclass const *quantclass, | |
205 | - mad_fixed_t output[3]) | |
206 | + mad_fixed_t output[3], struct mad_stream *stream) | |
207 | { | |
208 | unsigned int nb, s, sample[3]; | |
209 | + struct mad_bitptr frameend_ptr; | |
210 | + | |
211 | + mad_bit_init(&frameend_ptr, stream->next_frame); | |
212 | ||
213 | if ((nb = quantclass->group)) { | |
214 | unsigned int c, nlevels; | |
215 | ||
216 | + if (mad_bit_length(ptr, &frameend_ptr) < quantclass->bits) { | |
217 | + stream->error = MAD_ERROR_LOSTSYNC; | |
218 | + stream->sync = 0; | |
219 | + return; | |
220 | + } | |
221 | /* degrouping */ | |
222 | c = mad_bit_read(ptr, quantclass->bits); | |
223 | nlevels = quantclass->nlevels; | |
224 | @@ -299,8 +348,14 @@ void II_samples(struct mad_bitptr *ptr, | |
225 | else { | |
226 | nb = quantclass->bits; | |
227 | ||
228 | - for (s = 0; s < 3; ++s) | |
229 | + for (s = 0; s < 3; ++s) { | |
230 | + if (mad_bit_length(ptr, &frameend_ptr) < nb) { | |
231 | + stream->error = MAD_ERROR_LOSTSYNC; | |
232 | + stream->sync = 0; | |
233 | + return; | |
234 | + } | |
235 | sample[s] = mad_bit_read(ptr, nb); | |
236 | + } | |
237 | } | |
238 | ||
239 | for (s = 0; s < 3; ++s) { | |
240 | @@ -336,6 +391,9 @@ int mad_layer_II(struct mad_stream *stre | |
241 | unsigned char const *offsets; | |
242 | unsigned char allocation[2][32], scfsi[2][32], scalefactor[2][32][3]; | |
243 | mad_fixed_t samples[3]; | |
244 | + struct mad_bitptr frameend_ptr; | |
245 | + | |
246 | + mad_bit_init(&frameend_ptr, stream->next_frame); | |
247 | ||
248 | nch = MAD_NCHANNELS(header); | |
249 | ||
250 | @@ -402,13 +460,24 @@ int mad_layer_II(struct mad_stream *stre | |
251 | for (sb = 0; sb < bound; ++sb) { | |
252 | nbal = bitalloc_table[offsets[sb]].nbal; | |
253 | ||
254 | - for (ch = 0; ch < nch; ++ch) | |
255 | + for (ch = 0; ch < nch; ++ch) { | |
256 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < nbal) { | |
257 | + stream->error = MAD_ERROR_LOSTSYNC; | |
258 | + stream->sync = 0; | |
259 | + return -1; | |
260 | + } | |
261 | allocation[ch][sb] = mad_bit_read(&stream->ptr, nbal); | |
262 | + } | |
263 | } | |
264 | ||
265 | for (sb = bound; sb < sblimit; ++sb) { | |
266 | nbal = bitalloc_table[offsets[sb]].nbal; | |
267 | ||
268 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < nbal) { | |
269 | + stream->error = MAD_ERROR_LOSTSYNC; | |
270 | + stream->sync = 0; | |
271 | + return -1; | |
272 | + } | |
273 | allocation[0][sb] = | |
274 | allocation[1][sb] = mad_bit_read(&stream->ptr, nbal); | |
275 | } | |
276 | @@ -417,8 +486,14 @@ int mad_layer_II(struct mad_stream *stre | |
277 | ||
278 | for (sb = 0; sb < sblimit; ++sb) { | |
279 | for (ch = 0; ch < nch; ++ch) { | |
280 | - if (allocation[ch][sb]) | |
281 | + if (allocation[ch][sb]) { | |
282 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 2) { | |
283 | + stream->error = MAD_ERROR_LOSTSYNC; | |
284 | + stream->sync = 0; | |
285 | + return -1; | |
286 | + } | |
287 | scfsi[ch][sb] = mad_bit_read(&stream->ptr, 2); | |
288 | + } | |
289 | } | |
290 | } | |
291 | ||
292 | @@ -441,6 +516,11 @@ int mad_layer_II(struct mad_stream *stre | |
293 | for (sb = 0; sb < sblimit; ++sb) { | |
294 | for (ch = 0; ch < nch; ++ch) { | |
295 | if (allocation[ch][sb]) { | |
296 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 6) { | |
297 | + stream->error = MAD_ERROR_LOSTSYNC; | |
298 | + stream->sync = 0; | |
299 | + return -1; | |
300 | + } | |
301 | scalefactor[ch][sb][0] = mad_bit_read(&stream->ptr, 6); | |
302 | ||
303 | switch (scfsi[ch][sb]) { | |
304 | @@ -451,11 +531,21 @@ int mad_layer_II(struct mad_stream *stre | |
305 | break; | |
306 | ||
307 | case 0: | |
308 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 6) { | |
309 | + stream->error = MAD_ERROR_LOSTSYNC; | |
310 | + stream->sync = 0; | |
311 | + return -1; | |
312 | + } | |
313 | scalefactor[ch][sb][1] = mad_bit_read(&stream->ptr, 6); | |
314 | /* fall through */ | |
315 | ||
316 | case 1: | |
317 | case 3: | |
318 | + if (mad_bit_length(&stream->ptr, &frameend_ptr) < 6) { | |
319 | + stream->error = MAD_ERROR_LOSTSYNC; | |
320 | + stream->sync = 0; | |
321 | + return -1; | |
322 | + } | |
323 | scalefactor[ch][sb][2] = mad_bit_read(&stream->ptr, 6); | |
324 | } | |
325 | ||
326 | @@ -487,7 +577,9 @@ int mad_layer_II(struct mad_stream *stre | |
327 | if ((index = allocation[ch][sb])) { | |
328 | index = offset_table[bitalloc_table[offsets[sb]].offset][index - 1]; | |
329 | ||
330 | - II_samples(&stream->ptr, &qc_table[index], samples); | |
331 | + II_samples(&stream->ptr, &qc_table[index], samples, stream); | |
332 | + if (stream->error != 0) | |
333 | + return -1; | |
334 | ||
335 | for (s = 0; s < 3; ++s) { | |
336 | frame->sbsample[ch][3 * gr + s][sb] = | |
337 | @@ -505,7 +597,9 @@ int mad_layer_II(struct mad_stream *stre | |
338 | if ((index = allocation[0][sb])) { | |
339 | index = offset_table[bitalloc_table[offsets[sb]].offset][index - 1]; | |
340 | ||
341 | - II_samples(&stream->ptr, &qc_table[index], samples); | |
342 | + II_samples(&stream->ptr, &qc_table[index], samples, stream); | |
343 | + if (stream->error != 0) | |
344 | + return -1; | |
345 | ||
346 | for (ch = 0; ch < nch; ++ch) { | |
347 | for (s = 0; s < 3; ++s) { | |
348 | Index: libmad-0.15.1b/layer3.c | |
349 | =================================================================== | |
350 | --- libmad-0.15.1b.orig/layer3.c | |
351 | +++ libmad-0.15.1b/layer3.c | |
352 | @@ -598,7 +598,8 @@ enum mad_error III_sideinfo(struct mad_b | |
353 | static | |
354 | unsigned int III_scalefactors_lsf(struct mad_bitptr *ptr, | |
355 | struct channel *channel, | |
356 | - struct channel *gr1ch, int mode_extension) | |
357 | + struct channel *gr1ch, int mode_extension, | |
358 | + unsigned int bits_left, unsigned int *part2_length) | |
359 | { | |
360 | struct mad_bitptr start; | |
361 | unsigned int scalefac_compress, index, slen[4], part, n, i; | |
362 | @@ -644,8 +645,12 @@ unsigned int III_scalefactors_lsf(struct | |
363 | ||
364 | n = 0; | |
365 | for (part = 0; part < 4; ++part) { | |
366 | - for (i = 0; i < nsfb[part]; ++i) | |
367 | + for (i = 0; i < nsfb[part]; ++i) { | |
368 | + if (bits_left < slen[part]) | |
369 | + return MAD_ERROR_BADSCFSI; | |
370 | channel->scalefac[n++] = mad_bit_read(ptr, slen[part]); | |
371 | + bits_left -= slen[part]; | |
372 | + } | |
373 | } | |
374 | ||
375 | while (n < 39) | |
376 | @@ -690,7 +695,10 @@ unsigned int III_scalefactors_lsf(struct | |
377 | max = (1 << slen[part]) - 1; | |
378 | ||
379 | for (i = 0; i < nsfb[part]; ++i) { | |
380 | + if (bits_left < slen[part]) | |
381 | + return MAD_ERROR_BADSCFSI; | |
382 | is_pos = mad_bit_read(ptr, slen[part]); | |
383 | + bits_left -= slen[part]; | |
384 | ||
385 | channel->scalefac[n] = is_pos; | |
386 | gr1ch->scalefac[n++] = (is_pos == max); | |
387 | @@ -703,7 +711,8 @@ unsigned int III_scalefactors_lsf(struct | |
388 | } | |
389 | } | |
390 | ||
391 | - return mad_bit_length(&start, ptr); | |
392 | + *part2_length = mad_bit_length(&start, ptr); | |
393 | + return MAD_ERROR_NONE; | |
394 | } | |
395 | ||
396 | /* | |
397 | @@ -712,7 +721,8 @@ unsigned int III_scalefactors_lsf(struct | |
398 | */ | |
399 | static | |
400 | unsigned int III_scalefactors(struct mad_bitptr *ptr, struct channel *channel, | |
401 | - struct channel const *gr0ch, unsigned int scfsi) | |
402 | + struct channel const *gr0ch, unsigned int scfsi, | |
403 | + unsigned int bits_left, unsigned int *part2_length) | |
404 | { | |
405 | struct mad_bitptr start; | |
406 | unsigned int slen1, slen2, sfbi; | |
407 | @@ -728,12 +738,20 @@ unsigned int III_scalefactors(struct mad | |
408 | sfbi = 0; | |
409 | ||
410 | nsfb = (channel->flags & mixed_block_flag) ? 8 + 3 * 3 : 6 * 3; | |
411 | - while (nsfb--) | |
412 | + while (nsfb--) { | |
413 | + if (bits_left < slen1) | |
414 | + return MAD_ERROR_BADSCFSI; | |
415 | channel->scalefac[sfbi++] = mad_bit_read(ptr, slen1); | |
416 | + bits_left -= slen1; | |
417 | + } | |
418 | ||
419 | nsfb = 6 * 3; | |
420 | - while (nsfb--) | |
421 | + while (nsfb--) { | |
422 | + if (bits_left < slen2) | |
423 | + return MAD_ERROR_BADSCFSI; | |
424 | channel->scalefac[sfbi++] = mad_bit_read(ptr, slen2); | |
425 | + bits_left -= slen2; | |
426 | + } | |
427 | ||
428 | nsfb = 1 * 3; | |
429 | while (nsfb--) | |
430 | @@ -745,8 +763,12 @@ unsigned int III_scalefactors(struct mad | |
431 | channel->scalefac[sfbi] = gr0ch->scalefac[sfbi]; | |
432 | } | |
433 | else { | |
434 | - for (sfbi = 0; sfbi < 6; ++sfbi) | |
435 | + for (sfbi = 0; sfbi < 6; ++sfbi) { | |
436 | + if (bits_left < slen1) | |
437 | + return MAD_ERROR_BADSCFSI; | |
438 | channel->scalefac[sfbi] = mad_bit_read(ptr, slen1); | |
439 | + bits_left -= slen1; | |
440 | + } | |
441 | } | |
442 | ||
443 | if (scfsi & 0x4) { | |
444 | @@ -754,8 +776,12 @@ unsigned int III_scalefactors(struct mad | |
445 | channel->scalefac[sfbi] = gr0ch->scalefac[sfbi]; | |
446 | } | |
447 | else { | |
448 | - for (sfbi = 6; sfbi < 11; ++sfbi) | |
449 | + for (sfbi = 6; sfbi < 11; ++sfbi) { | |
450 | + if (bits_left < slen1) | |
451 | + return MAD_ERROR_BADSCFSI; | |
452 | channel->scalefac[sfbi] = mad_bit_read(ptr, slen1); | |
453 | + bits_left -= slen1; | |
454 | + } | |
455 | } | |
456 | ||
457 | if (scfsi & 0x2) { | |
458 | @@ -763,8 +789,12 @@ unsigned int III_scalefactors(struct mad | |
459 | channel->scalefac[sfbi] = gr0ch->scalefac[sfbi]; | |
460 | } | |
461 | else { | |
462 | - for (sfbi = 11; sfbi < 16; ++sfbi) | |
463 | + for (sfbi = 11; sfbi < 16; ++sfbi) { | |
464 | + if (bits_left < slen2) | |
465 | + return MAD_ERROR_BADSCFSI; | |
466 | channel->scalefac[sfbi] = mad_bit_read(ptr, slen2); | |
467 | + bits_left -= slen2; | |
468 | + } | |
469 | } | |
470 | ||
471 | if (scfsi & 0x1) { | |
472 | @@ -772,14 +802,19 @@ unsigned int III_scalefactors(struct mad | |
473 | channel->scalefac[sfbi] = gr0ch->scalefac[sfbi]; | |
474 | } | |
475 | else { | |
476 | - for (sfbi = 16; sfbi < 21; ++sfbi) | |
477 | + for (sfbi = 16; sfbi < 21; ++sfbi) { | |
478 | + if (bits_left < slen2) | |
479 | + return MAD_ERROR_BADSCFSI; | |
480 | channel->scalefac[sfbi] = mad_bit_read(ptr, slen2); | |
481 | + bits_left -= slen2; | |
482 | + } | |
483 | } | |
484 | ||
485 | channel->scalefac[21] = 0; | |
486 | } | |
487 | ||
488 | - return mad_bit_length(&start, ptr); | |
489 | + *part2_length = mad_bit_length(&start, ptr); | |
490 | + return MAD_ERROR_NONE; | |
491 | } | |
492 | ||
493 | /* | |
494 | @@ -933,19 +968,17 @@ static | |
495 | enum mad_error III_huffdecode(struct mad_bitptr *ptr, mad_fixed_t xr[576], | |
496 | struct channel *channel, | |
497 | unsigned char const *sfbwidth, | |
498 | - unsigned int part2_length) | |
499 | + signed int part3_length) | |
500 | { | |
501 | signed int exponents[39], exp; | |
502 | signed int const *expptr; | |
503 | struct mad_bitptr peek; | |
504 | - signed int bits_left, cachesz; | |
505 | + signed int bits_left, cachesz, fakebits; | |
506 | register mad_fixed_t *xrptr; | |
507 | mad_fixed_t const *sfbound; | |
508 | register unsigned long bitcache; | |
509 | ||
510 | - bits_left = (signed) channel->part2_3_length - (signed) part2_length; | |
511 | - if (bits_left < 0) | |
512 | - return MAD_ERROR_BADPART3LEN; | |
513 | + bits_left = part3_length; | |
514 | ||
515 | III_exponents(channel, sfbwidth, exponents); | |
516 | ||
517 | @@ -956,8 +989,12 @@ enum mad_error III_huffdecode(struct mad | |
518 | cachesz = mad_bit_bitsleft(&peek); | |
519 | cachesz += ((32 - 1 - 24) + (24 - cachesz)) & ~7; | |
520 | ||
521 | + if (bits_left < cachesz) { | |
522 | + cachesz = bits_left; | |
523 | + } | |
524 | bitcache = mad_bit_read(&peek, cachesz); | |
525 | bits_left -= cachesz; | |
526 | + fakebits = 0; | |
527 | ||
528 | xrptr = &xr[0]; | |
529 | ||
530 | @@ -986,7 +1023,7 @@ enum mad_error III_huffdecode(struct mad | |
531 | ||
532 | big_values = channel->big_values; | |
533 | ||
534 | - while (big_values-- && cachesz + bits_left > 0) { | |
535 | + while (big_values-- && cachesz + bits_left - fakebits > 0) { | |
536 | union huffpair const *pair; | |
537 | unsigned int clumpsz, value; | |
538 | register mad_fixed_t requantized; | |
539 | @@ -1023,10 +1060,19 @@ enum mad_error III_huffdecode(struct mad | |
540 | unsigned int bits; | |
541 | ||
542 | bits = ((32 - 1 - 21) + (21 - cachesz)) & ~7; | |
543 | + if (bits_left < bits) { | |
544 | + bits = bits_left; | |
545 | + } | |
546 | bitcache = (bitcache << bits) | mad_bit_read(&peek, bits); | |
547 | cachesz += bits; | |
548 | bits_left -= bits; | |
549 | } | |
550 | + if (cachesz < 21) { | |
551 | + unsigned int bits = 21 - cachesz; | |
552 | + bitcache <<= bits; | |
553 | + cachesz += bits; | |
554 | + fakebits += bits; | |
555 | + } | |
556 | ||
557 | /* hcod (0..19) */ | |
558 | ||
559 | @@ -1041,6 +1087,8 @@ enum mad_error III_huffdecode(struct mad | |
560 | } | |
561 | ||
562 | cachesz -= pair->value.hlen; | |
563 | + if (cachesz < fakebits) | |
564 | + return MAD_ERROR_BADHUFFDATA; | |
565 | ||
566 | if (linbits) { | |
567 | /* x (0..14) */ | |
568 | @@ -1054,10 +1102,15 @@ enum mad_error III_huffdecode(struct mad | |
569 | ||
570 | case 15: | |
571 | if (cachesz < linbits + 2) { | |
572 | - bitcache = (bitcache << 16) | mad_bit_read(&peek, 16); | |
573 | - cachesz += 16; | |
574 | - bits_left -= 16; | |
575 | + unsigned int bits = 16; | |
576 | + if (bits_left < 16) | |
577 | + bits = bits_left; | |
578 | + bitcache = (bitcache << bits) | mad_bit_read(&peek, bits); | |
579 | + cachesz += bits; | |
580 | + bits_left -= bits; | |
581 | } | |
582 | + if (cachesz - fakebits < linbits) | |
583 | + return MAD_ERROR_BADHUFFDATA; | |
584 | ||
585 | value += MASK(bitcache, cachesz, linbits); | |
586 | cachesz -= linbits; | |
587 | @@ -1074,6 +1127,8 @@ enum mad_error III_huffdecode(struct mad | |
588 | } | |
589 | ||
590 | x_final: | |
591 | + if (cachesz - fakebits < 1) | |
592 | + return MAD_ERROR_BADHUFFDATA; | |
593 | xrptr[0] = MASK1BIT(bitcache, cachesz--) ? | |
594 | -requantized : requantized; | |
595 | } | |
596 | @@ -1089,10 +1144,15 @@ enum mad_error III_huffdecode(struct mad | |
597 | ||
598 | case 15: | |
599 | if (cachesz < linbits + 1) { | |
600 | - bitcache = (bitcache << 16) | mad_bit_read(&peek, 16); | |
601 | - cachesz += 16; | |
602 | - bits_left -= 16; | |
603 | + unsigned int bits = 16; | |
604 | + if (bits_left < 16) | |
605 | + bits = bits_left; | |
606 | + bitcache = (bitcache << bits) | mad_bit_read(&peek, bits); | |
607 | + cachesz += bits; | |
608 | + bits_left -= bits; | |
609 | } | |
610 | + if (cachesz - fakebits < linbits) | |
611 | + return MAD_ERROR_BADHUFFDATA; | |
612 | ||
613 | value += MASK(bitcache, cachesz, linbits); | |
614 | cachesz -= linbits; | |
615 | @@ -1109,6 +1169,8 @@ enum mad_error III_huffdecode(struct mad | |
616 | } | |
617 | ||
618 | y_final: | |
619 | + if (cachesz - fakebits < 1) | |
620 | + return MAD_ERROR_BADHUFFDATA; | |
621 | xrptr[1] = MASK1BIT(bitcache, cachesz--) ? | |
622 | -requantized : requantized; | |
623 | } | |
624 | @@ -1128,6 +1190,8 @@ enum mad_error III_huffdecode(struct mad | |
625 | requantized = reqcache[value] = III_requantize(value, exp); | |
626 | } | |
627 | ||
628 | + if (cachesz - fakebits < 1) | |
629 | + return MAD_ERROR_BADHUFFDATA; | |
630 | xrptr[0] = MASK1BIT(bitcache, cachesz--) ? | |
631 | -requantized : requantized; | |
632 | } | |
633 | @@ -1146,6 +1210,8 @@ enum mad_error III_huffdecode(struct mad | |
634 | requantized = reqcache[value] = III_requantize(value, exp); | |
635 | } | |
636 | ||
637 | + if (cachesz - fakebits < 1) | |
638 | + return MAD_ERROR_BADHUFFDATA; | |
639 | xrptr[1] = MASK1BIT(bitcache, cachesz--) ? | |
640 | -requantized : requantized; | |
641 | } | |
642 | @@ -1155,9 +1221,6 @@ enum mad_error III_huffdecode(struct mad | |
643 | } | |
644 | } | |
645 | ||
646 | - if (cachesz + bits_left < 0) | |
647 | - return MAD_ERROR_BADHUFFDATA; /* big_values overrun */ | |
648 | - | |
649 | /* count1 */ | |
650 | { | |
651 | union huffquad const *table; | |
652 | @@ -1167,15 +1230,24 @@ enum mad_error III_huffdecode(struct mad | |
653 | ||
654 | requantized = III_requantize(1, exp); | |
655 | ||
656 | - while (cachesz + bits_left > 0 && xrptr <= &xr[572]) { | |
657 | + while (cachesz + bits_left - fakebits > 0 && xrptr <= &xr[572]) { | |
658 | union huffquad const *quad; | |
659 | ||
660 | /* hcod (1..6) */ | |
661 | ||
662 | if (cachesz < 10) { | |
663 | - bitcache = (bitcache << 16) | mad_bit_read(&peek, 16); | |
664 | - cachesz += 16; | |
665 | - bits_left -= 16; | |
666 | + unsigned int bits = 16; | |
667 | + if (bits_left < 16) | |
668 | + bits = bits_left; | |
669 | + bitcache = (bitcache << bits) | mad_bit_read(&peek, bits); | |
670 | + cachesz += bits; | |
671 | + bits_left -= bits; | |
672 | + } | |
673 | + if (cachesz < 10) { | |
674 | + unsigned int bits = 10 - cachesz; | |
675 | + bitcache <<= bits; | |
676 | + cachesz += bits; | |
677 | + fakebits += bits; | |
678 | } | |
679 | ||
680 | quad = &table[MASK(bitcache, cachesz, 4)]; | |
681 | @@ -1188,6 +1260,11 @@ enum mad_error III_huffdecode(struct mad | |
682 | MASK(bitcache, cachesz, quad->ptr.bits)]; | |
683 | } | |
684 | ||
685 | + if (cachesz - fakebits < quad->value.hlen + quad->value.v | |
686 | + + quad->value.w + quad->value.x + quad->value.y) | |
687 | + /* We don't have enough bits to read one more entry, consider them | |
688 | + * stuffing bits. */ | |
689 | + break; | |
690 | cachesz -= quad->value.hlen; | |
691 | ||
692 | if (xrptr == sfbound) { | |
693 | @@ -1236,22 +1313,8 @@ enum mad_error III_huffdecode(struct mad | |
694 | ||
695 | xrptr += 2; | |
696 | } | |
697 | - | |
698 | - if (cachesz + bits_left < 0) { | |
699 | -# if 0 && defined(DEBUG) | |
700 | - fprintf(stderr, "huffman count1 overrun (%d bits)\n", | |
701 | - -(cachesz + bits_left)); | |
702 | -# endif | |
703 | - | |
704 | - /* technically the bitstream is misformatted, but apparently | |
705 | - some encoders are just a bit sloppy with stuffing bits */ | |
706 | - | |
707 | - xrptr -= 4; | |
708 | - } | |
709 | } | |
710 | ||
711 | - assert(-bits_left <= MAD_BUFFER_GUARD * CHAR_BIT); | |
712 | - | |
713 | # if 0 && defined(DEBUG) | |
714 | if (bits_left < 0) | |
715 | fprintf(stderr, "read %d bits too many\n", -bits_left); | |
716 | @@ -2348,10 +2411,11 @@ void III_freqinver(mad_fixed_t sample[18 | |
717 | */ | |
718 | static | |
719 | enum mad_error III_decode(struct mad_bitptr *ptr, struct mad_frame *frame, | |
720 | - struct sideinfo *si, unsigned int nch) | |
721 | + struct sideinfo *si, unsigned int nch, unsigned int md_len) | |
722 | { | |
723 | struct mad_header *header = &frame->header; | |
724 | unsigned int sfreqi, ngr, gr; | |
725 | + int bits_left = md_len * CHAR_BIT; | |
726 | ||
727 | { | |
728 | unsigned int sfreq; | |
729 | @@ -2383,6 +2447,7 @@ enum mad_error III_decode(struct mad_bit | |
730 | for (ch = 0; ch < nch; ++ch) { | |
731 | struct channel *channel = &granule->ch[ch]; | |
732 | unsigned int part2_length; | |
733 | + unsigned int part3_length; | |
734 | ||
735 | sfbwidth[ch] = sfbwidth_table[sfreqi].l; | |
736 | if (channel->block_type == 2) { | |
737 | @@ -2391,18 +2456,30 @@ enum mad_error III_decode(struct mad_bit | |
738 | } | |
739 | ||
740 | if (header->flags & MAD_FLAG_LSF_EXT) { | |
741 | - part2_length = III_scalefactors_lsf(ptr, channel, | |
742 | + error = III_scalefactors_lsf(ptr, channel, | |
743 | ch == 0 ? 0 : &si->gr[1].ch[1], | |
744 | - header->mode_extension); | |
745 | + header->mode_extension, bits_left, &part2_length); | |
746 | } | |
747 | else { | |
748 | - part2_length = III_scalefactors(ptr, channel, &si->gr[0].ch[ch], | |
749 | - gr == 0 ? 0 : si->scfsi[ch]); | |
750 | + error = III_scalefactors(ptr, channel, &si->gr[0].ch[ch], | |
751 | + gr == 0 ? 0 : si->scfsi[ch], bits_left, &part2_length); | |
752 | } | |
753 | + if (error) | |
754 | + return error; | |
755 | + | |
756 | + bits_left -= part2_length; | |
757 | ||
758 | - error = III_huffdecode(ptr, xr[ch], channel, sfbwidth[ch], part2_length); | |
759 | + if (part2_length > channel->part2_3_length) | |
760 | + return MAD_ERROR_BADPART3LEN; | |
761 | + | |
762 | + part3_length = channel->part2_3_length - part2_length; | |
763 | + if (part3_length > bits_left) | |
764 | + return MAD_ERROR_BADPART3LEN; | |
765 | + | |
766 | + error = III_huffdecode(ptr, xr[ch], channel, sfbwidth[ch], part3_length); | |
767 | if (error) | |
768 | return error; | |
769 | + bits_left -= part3_length; | |
770 | } | |
771 | ||
772 | /* joint stereo processing */ | |
773 | @@ -2519,11 +2596,13 @@ int mad_layer_III(struct mad_stream *str | |
774 | unsigned int nch, priv_bitlen, next_md_begin = 0; | |
775 | unsigned int si_len, data_bitlen, md_len; | |
776 | unsigned int frame_space, frame_used, frame_free; | |
777 | - struct mad_bitptr ptr; | |
778 | + struct mad_bitptr ptr, bufend_ptr; | |
779 | struct sideinfo si; | |
780 | enum mad_error error; | |
781 | int result = 0; | |
782 | ||
783 | + mad_bit_init(&bufend_ptr, stream->bufend); | |
784 | + | |
785 | /* allocate Layer III dynamic structures */ | |
786 | ||
787 | if (stream->main_data == 0) { | |
788 | @@ -2587,14 +2666,15 @@ int mad_layer_III(struct mad_stream *str | |
789 | unsigned long header; | |
790 | ||
791 | mad_bit_init(&peek, stream->next_frame); | |
792 | + if (mad_bit_length(&peek, &bufend_ptr) >= 57) { | |
793 | + header = mad_bit_read(&peek, 32); | |
794 | + if ((header & 0xffe60000L) /* syncword | layer */ == 0xffe20000L) { | |
795 | + if (!(header & 0x00010000L)) /* protection_bit */ | |
796 | + mad_bit_skip(&peek, 16); /* crc_check */ | |
797 | ||
798 | - header = mad_bit_read(&peek, 32); | |
799 | - if ((header & 0xffe60000L) /* syncword | layer */ == 0xffe20000L) { | |
800 | - if (!(header & 0x00010000L)) /* protection_bit */ | |
801 | - mad_bit_skip(&peek, 16); /* crc_check */ | |
802 | - | |
803 | - next_md_begin = | |
804 | - mad_bit_read(&peek, (header & 0x00080000L) /* ID */ ? 9 : 8); | |
805 | + next_md_begin = | |
806 | + mad_bit_read(&peek, (header & 0x00080000L) /* ID */ ? 9 : 8); | |
807 | + } | |
808 | } | |
809 | ||
810 | mad_bit_finish(&peek); | |
811 | @@ -2653,7 +2733,7 @@ int mad_layer_III(struct mad_stream *str | |
812 | /* decode main_data */ | |
813 | ||
814 | if (result == 0) { | |
815 | - error = III_decode(&ptr, frame, &si, nch); | |
816 | + error = III_decode(&ptr, frame, &si, nch, md_len); | |
817 | if (error) { | |
818 | stream->error = error; | |
819 | result = -1; |