2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 /* Targeted fuzzer that targets specific codecs depending on two
23 * Get the very fresh clang, e.g. see http://libfuzzer.info#versions
24 * Get and build libFuzzer:
25 svn co http://llvm.org/svn/llvm-project/llvm/trunk/lib/Fuzzer
27 * build ffmpeg for fuzzing:
28 FLAGS="-fsanitize=address -fsanitize-coverage=trace-pc-guard,trace-cmp -g" CC="clang $FLAGS" CXX="clang++ $FLAGS" ./configure --disable-x86asm
30 * build the fuzz target.
31 Choose the value of FFMPEG_CODEC (e.g. AV_CODEC_ID_DVD_SUBTITLE) and
32 choose one of FUZZ_FFMPEG_VIDEO, FUZZ_FFMPEG_AUDIO, FUZZ_FFMPEG_SUBTITLE.
33 clang -fsanitize=address -fsanitize-coverage=trace-pc-guard,trace-cmp tools/target_dec_fuzzer.c -o target_dec_fuzzer -I. -DFFMPEG_CODEC=AV_CODEC_ID_MPEG1VIDEO -DFUZZ_FFMPEG_VIDEO ../../libfuzzer/libFuzzer.a -Llibavcodec -Llibavdevice -Llibavfilter -Llibavformat -Llibavresample -Llibavutil -Llibpostproc -Llibswscale -Llibswresample -Wl,--as-needed -Wl,-z,noexecstack -Wl,--warn-common -Wl,-rpath-link=:libpostproc:libswresample:libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample -lavdevice -lavfilter -lavformat -lavcodec -lswresample -lswscale -lavutil -ldl -lxcb -lxcb-shm -lxcb -lxcb-xfixes -lxcb -lxcb-shape -lxcb -lX11 -lasound -lm -lbz2 -lz -pthread
34 * create a corpus directory and put some samples there (empty dir is ok too):
35 mkdir CORPUS && cp some-files CORPUS
38 ./target_dec_fuzzer -max_len=100000 CORPUS
42 http://tutorial.libfuzzer.info
43 https://github.com/google/oss-fuzz
44 http://lcamtuf.coredump.cx/afl/
45 https://security.googleblog.com/2016/08/guided-in-process-fuzzing-of-chrome.html
49 #include "libavutil/avassert.h"
50 #include "libavutil/imgutils.h"
51 #include "libavutil/intreadwrite.h"
53 #include "libavcodec/avcodec.h"
54 #include "libavcodec/bytestream.h"
55 #include "libavformat/avformat.h"
57 //For FF_SANE_NB_CHANNELS, so we dont waste energy testing things that will get instantly rejected
58 #include "libavcodec/internal.h"
60 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
62 extern AVCodec * codec_list[];
64 static void error(const char *err)
66 fprintf(stderr, "%s", err);
70 static AVCodec *c = NULL;
71 static AVCodec *AVCodecInitialize(enum AVCodecID codec_id)
75 res = avcodec_find_decoder(codec_id);
77 error("Failed to find decoder");
81 static int subtitle_handler(AVCodecContext *avctx, void *frame,
82 int *got_sub_ptr, AVPacket *avpkt)
85 int ret = avcodec_decode_subtitle2(avctx, &sub, got_sub_ptr, avpkt);
86 if (ret >= 0 && *got_sub_ptr)
87 avsubtitle_free(&sub);
91 // Ensure we don't loop forever
92 const uint32_t maxiteration = 8096;
93 const uint64_t maxpixels_per_frame = 4096 * 4096;
96 const uint64_t maxsamples_per_frame = 256*1024*32;
99 static const uint64_t FUZZ_TAG = 0x4741542D5A5A5546ULL;
101 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
102 const uint64_t fuzz_tag = FUZZ_TAG;
103 const uint8_t *last = data;
104 const uint8_t *end = data + size;
106 uint64_t ec_pixels = 0;
107 uint64_t nb_samples = 0;
108 int (*decode_handler)(AVCodecContext *avctx, AVFrame *picture,
109 int *got_picture_ptr,
110 const AVPacket *avpkt) = NULL;
111 AVCodecParserContext *parser = NULL;
112 uint64_t keyframes = 0;
113 AVDictionary *opts = NULL;
116 #ifdef FFMPEG_DECODER
117 #define DECODER_SYMBOL0(CODEC) ff_##CODEC##_decoder
118 #define DECODER_SYMBOL(CODEC) DECODER_SYMBOL0(CODEC)
119 extern AVCodec DECODER_SYMBOL(FFMPEG_DECODER);
120 codec_list[0] = &DECODER_SYMBOL(FFMPEG_DECODER);
121 avcodec_register(&DECODER_SYMBOL(FFMPEG_DECODER));
123 c = &DECODER_SYMBOL(FFMPEG_DECODER);
125 avcodec_register_all();
126 c = AVCodecInitialize(FFMPEG_CODEC); // Done once.
128 av_log_set_level(AV_LOG_PANIC);
132 case AVMEDIA_TYPE_AUDIO : decode_handler = avcodec_decode_audio4; break;
133 case AVMEDIA_TYPE_VIDEO : decode_handler = avcodec_decode_video2; break;
134 case AVMEDIA_TYPE_SUBTITLE: decode_handler = subtitle_handler ; break;
136 maxpixels = maxpixels_per_frame * maxiteration;
137 maxsamples = maxsamples_per_frame * maxiteration;
139 // Allows a small input to generate gigantic output
140 case AV_CODEC_ID_BINKVIDEO: maxpixels /= 32; break;
141 case AV_CODEC_ID_CFHD: maxpixels /= 128; break;
142 case AV_CODEC_ID_DIRAC: maxpixels /= 8192; break;
143 case AV_CODEC_ID_DST: maxsamples /= 8192; break;
144 case AV_CODEC_ID_DXV: maxpixels /= 32; break;
145 case AV_CODEC_ID_FFWAVESYNTH: maxsamples /= 16384; break;
146 case AV_CODEC_ID_MSRLE: maxpixels /= 16; break;
147 case AV_CODEC_ID_QTRLE: maxpixels /= 16; break;
148 case AV_CODEC_ID_RASC: maxpixels /= 16; break;
149 case AV_CODEC_ID_SANM: maxpixels /= 16; break;
150 case AV_CODEC_ID_G2M: maxpixels /= 64; break;
151 case AV_CODEC_ID_GIF: maxpixels /= 16; break;
152 // Performs slow frame rescaling in C
153 case AV_CODEC_ID_GDV: maxpixels /= 512; break;
154 // Postprocessing in C
155 case AV_CODEC_ID_HNM4_VIDEO:maxpixels /= 128; break;
156 // Cliping in C, generally slow even with small input
157 case AV_CODEC_ID_INDEO4: maxpixels /= 128; break;
158 case AV_CODEC_ID_LSCR: maxpixels /= 16; break;
159 case AV_CODEC_ID_MOTIONPIXELS:maxpixels /= 256; break;
160 case AV_CODEC_ID_MSS2: maxpixels /= 16384; break;
161 case AV_CODEC_ID_MSZH: maxpixels /= 128; break;
162 case AV_CODEC_ID_SCPR: maxpixels /= 32; break;
163 case AV_CODEC_ID_SMACKVIDEO: maxpixels /= 64; break;
164 case AV_CODEC_ID_SNOW: maxpixels /= 128; break;
165 case AV_CODEC_ID_TGV: maxpixels /= 32; break;
166 case AV_CODEC_ID_TRUEMOTION2: maxpixels /= 1024; break;
167 case AV_CODEC_ID_VP7: maxpixels /= 256; break;
168 case AV_CODEC_ID_VP9: maxpixels /= 4096; break;
172 AVCodecContext* ctx = avcodec_alloc_context3(c);
173 AVCodecContext* parser_avctx = avcodec_alloc_context3(NULL);
174 if (!ctx || !parser_avctx)
175 error("Failed memory allocation");
177 if (ctx->max_pixels == 0 || ctx->max_pixels > maxpixels_per_frame)
178 ctx->max_pixels = maxpixels_per_frame; //To reduce false positive OOM and hangs
179 ctx->refcounted_frames = 1; //To reduce false positive timeouts and focus testing on the refcounted API
181 ctx->max_samples = maxsamples_per_frame;
188 bytestream2_init(&gbc, data + size, 1024);
189 ctx->width = bytestream2_get_le32(&gbc);
190 ctx->height = bytestream2_get_le32(&gbc);
191 ctx->bit_rate = bytestream2_get_le64(&gbc);
192 ctx->bits_per_coded_sample = bytestream2_get_le32(&gbc);
193 // Try to initialize a parser for this codec, note, this may fail which just means we test without one
194 flags = bytestream2_get_byte(&gbc);
196 parser = av_parser_init(c->id);
198 ctx->strict_std_compliance = FF_COMPLIANCE_EXPERIMENTAL;
200 ctx->err_recognition = AV_EF_AGGRESSIVE | AV_EF_COMPLIANT | AV_EF_CAREFUL;
202 ctx->err_recognition |= AV_EF_EXPLODE;
205 ctx->flags2 |= AV_CODEC_FLAG2_FAST;
208 av_force_cpu_flags(0);
210 extradata_size = bytestream2_get_le32(&gbc);
212 ctx->sample_rate = bytestream2_get_le32(&gbc) & 0x7FFFFFFF;
213 ctx->channels = (unsigned)bytestream2_get_le32(&gbc) % FF_SANE_NB_CHANNELS;
214 ctx->block_align = bytestream2_get_le32(&gbc) & 0x7FFFFFFF;
215 ctx->codec_tag = bytestream2_get_le32(&gbc);
216 keyframes = bytestream2_get_le64(&gbc);
217 ctx->request_channel_layout = bytestream2_get_le64(&gbc);
219 ctx->idct_algo = bytestream2_get_byte(&gbc) % 25;
222 switch (ctx->codec_id) {
223 case AV_CODEC_ID_AC3:
224 case AV_CODEC_ID_EAC3:
225 av_dict_set_int(&opts, "cons_noisegen", bytestream2_get_byte(&gbc) & 1, 0);
226 av_dict_set_int(&opts, "heavy_compr", bytestream2_get_byte(&gbc) & 1, 0);
227 av_dict_set_int(&opts, "target_level", (int)(bytestream2_get_byte(&gbc) % 32) - 31, 0);
228 av_dict_set_int(&opts, "dmix_mode", (int)(bytestream2_get_byte(&gbc) % 4) - 1, 0);
234 if (extradata_size < size) {
235 ctx->extradata = av_mallocz(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
236 if (ctx->extradata) {
237 ctx->extradata_size = extradata_size;
238 size -= ctx->extradata_size;
239 memcpy(ctx->extradata, data + size, ctx->extradata_size);
242 if (av_image_check_size(ctx->width, ctx->height, 0, ctx))
243 ctx->width = ctx->height = 0;
246 int res = avcodec_open2(ctx, c, &opts);
248 avcodec_free_context(&ctx);
249 av_free(parser_avctx);
250 av_parser_close(parser);
252 return 0; // Failure of avcodec_open2() does not imply that a issue was found
254 parser_avctx->codec_id = ctx->codec_id;
257 AVFrame *frame = av_frame_alloc();
259 error("Failed memory allocation");
261 // Read very simple container
262 AVPacket avpkt, parsepkt;
263 av_init_packet(&avpkt);
264 av_init_packet(&parsepkt);
265 while (data < end && it < maxiteration) {
266 // Search for the TAG
267 while (data + sizeof(fuzz_tag) < end) {
268 if (data[0] == (fuzz_tag & 0xFF) && AV_RN64(data) == fuzz_tag)
272 if (data + sizeof(fuzz_tag) > end)
275 res = av_new_packet(&parsepkt, data - last);
277 error("Failed memory allocation");
278 memcpy(parsepkt.data, last, data - last);
279 parsepkt.flags = (keyframes & 1) * AV_PKT_FLAG_DISCARD + (!!(keyframes & 2)) * AV_PKT_FLAG_KEY;
280 keyframes = (keyframes >> 2) + (keyframes<<62);
281 data += sizeof(fuzz_tag);
284 while (parsepkt.size > 0) {
287 av_init_packet(&avpkt);
288 int ret = av_parser_parse2(parser, parser_avctx, &avpkt.data, &avpkt.size,
289 parsepkt.data, parsepkt.size,
290 parsepkt.pts, parsepkt.dts, parsepkt.pos);
291 if (avpkt.data == parsepkt.data) {
292 avpkt.buf = av_buffer_ref(parsepkt.buf);
294 error("Failed memory allocation");
296 if (av_packet_make_refcounted(&avpkt) < 0)
297 error("Failed memory allocation");
299 parsepkt.data += ret;
300 parsepkt.size -= ret;
302 avpkt.pts = parser->pts;
303 avpkt.dts = parser->dts;
304 avpkt.pos = parser->pos;
305 if ( parser->key_frame == 1 ||
306 (parser->key_frame == -1 && parser->pict_type == AV_PICTURE_TYPE_I))
307 avpkt.flags |= AV_PKT_FLAG_KEY;
308 avpkt.flags |= parsepkt.flags & AV_PKT_FLAG_DISCARD;
310 av_packet_move_ref(&avpkt, &parsepkt);
313 // Iterate through all data
314 while (avpkt.size > 0 && it++ < maxiteration) {
315 av_frame_unref(frame);
316 int ret = decode_handler(ctx, frame, &got_frame, &avpkt);
318 ec_pixels += (ctx->width + 32LL) * (ctx->height + 32LL);
319 if (it > 20 || ec_pixels > 4 * ctx->max_pixels)
320 ctx->error_concealment = 0;
321 if (ec_pixels > maxpixels)
322 goto maximums_reached;
324 nb_samples += frame->nb_samples;
325 if (nb_samples > maxsamples)
326 goto maximums_reached;
328 if (ret <= 0 || ret > avpkt.size)
330 if (ctx->codec_type != AVMEDIA_TYPE_AUDIO)
335 av_packet_unref(&avpkt);
337 av_packet_unref(&parsepkt);
341 av_packet_unref(&avpkt);
345 av_frame_unref(frame);
346 decode_handler(ctx, frame, &got_frame, &avpkt);
347 } while (got_frame == 1 && it++ < maxiteration);
349 fprintf(stderr, "pixels decoded: %"PRId64", samples decoded: %"PRId64", iterations: %d\n", ec_pixels, nb_samples, it);
351 av_frame_free(&frame);
352 avcodec_free_context(&ctx);
353 avcodec_free_context(&parser_avctx);
354 av_parser_close(parser);
355 av_packet_unref(&parsepkt);