| Message ID | 20210814150800.13974-2-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel,1/2] avcodec/snowdec: Cleanup avmv on errors | expand |
| Context | Check | Description |
|---|---|---|
| andriy/x86_make | success | Make finished |
| andriy/x86_make_fate | fail | Make fate failed |
| andriy/PPC64_make | success | Make finished |
| andriy/PPC64_make_fate | warning | Make fate failed |
On Sat, Aug 14, 2021 at 05:08:00PM +0200, Michael Niedermayer wrote: > Fixes: left shift of 16711968 by 8 places cannot be represented in type 'int' > Fixes: 36601/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-6581933285965824 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/h264_parser.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) will apply [...]
Michael Niedermayer: > Fixes: left shift of 16711968 by 8 places cannot be represented in type 'int' > Fixes: 36601/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-6581933285965824 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/h264_parser.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c > index d3c56cc188..22111c62a2 100644 > --- a/libavcodec/h264_parser.c > +++ b/libavcodec/h264_parser.c > @@ -86,7 +86,7 @@ static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf, > int nalsize = 0; > i = next_avc; > for (j = 0; j < p->nal_length_size; j++) > - nalsize = (nalsize << 8) | buf[i++]; > + nalsize = ((unsigned)nalsize << 8) | buf[i++]; > if (nalsize <= 0 || nalsize > buf_size - i) { > av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i); > return buf_size; > Makes me wonder why I never applied this: https://patchwork.ffmpeg.org/project/ffmpeg/patch/20200529161755.9904-1-andreas.rheinhardt@gmail.com/ (Your fix would only fix the undefined behaviour, not the nonsense logmessage (with negative sizes) one gets in this scenarion.) - Andreas
On Mon, Aug 16, 2021 at 11:31:15PM +0200, Andreas Rheinhardt wrote: > Michael Niedermayer: > > Fixes: left shift of 16711968 by 8 places cannot be represented in type 'int' > > Fixes: 36601/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-6581933285965824 > > > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > > --- > > libavcodec/h264_parser.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c > > index d3c56cc188..22111c62a2 100644 > > --- a/libavcodec/h264_parser.c > > +++ b/libavcodec/h264_parser.c > > @@ -86,7 +86,7 @@ static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf, > > int nalsize = 0; > > i = next_avc; > > for (j = 0; j < p->nal_length_size; j++) > > - nalsize = (nalsize << 8) | buf[i++]; > > + nalsize = ((unsigned)nalsize << 8) | buf[i++]; > > if (nalsize <= 0 || nalsize > buf_size - i) { > > av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i); > > return buf_size; > > > Makes me wonder why I never applied this: > https://patchwork.ffmpeg.org/project/ffmpeg/patch/20200529161755.9904-1-andreas.rheinhardt@gmail.com/ > (Your fix would only fix the undefined behaviour, not the nonsense > logmessage (with negative sizes) one gets in this scenarion.) if there was no reason why it wasnt applied then please apply and backport your fix thx [...]
diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c index d3c56cc188..22111c62a2 100644 --- a/libavcodec/h264_parser.c +++ b/libavcodec/h264_parser.c @@ -86,7 +86,7 @@ static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf, int nalsize = 0; i = next_avc; for (j = 0; j < p->nal_length_size; j++) - nalsize = (nalsize << 8) | buf[i++]; + nalsize = ((unsigned)nalsize << 8) | buf[i++]; if (nalsize <= 0 || nalsize > buf_size - i) { av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %d remaining %d\n", nalsize, buf_size - i); return buf_size;
Fixes: left shift of 16711968 by 8 places cannot be represented in type 'int' Fixes: 36601/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-6581933285965824 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/h264_parser.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)