Message ID | 20200529161755.9904-1-andreas.rheinhardt@gmail.com |
---|---|
State | Accepted |
Commit | c83a7dd25fdf9636e7e5da3fad5e0d82035b9c86 |
Headers | show |
Series | [FFmpeg-devel,1/2] avcodec/h264_parser: Fix undefined left shift | expand |
Context | Check | Description |
---|---|---|
andriy/default | pending | |
andriy/make | success | Make finished |
andriy/make_fate | success | Make fate finished |
On Fri, May 29, 2020 at 06:17:54PM +0200, Andreas Rheinhardt wrote: > Use an uint32_t for the NAL unit size of an AVC H.264 NAL unit instead > of an int as a left shift of a signed value is undefined behaviour > if the result doesn't fit into the target type. > > Also make the log message never output negative lengths. > > Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com> > --- > libavcodec/h264_parser.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) probably ok thx [...]
diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c index d9249e578d..1d2ce3870c 100644 --- a/libavcodec/h264_parser.c +++ b/libavcodec/h264_parser.c @@ -84,12 +84,13 @@ static int h264_find_frame_end(H264ParseContext *p, const uint8_t *buf, for (i = 0; i < buf_size; i++) { if (i >= next_avc) { - int nalsize = 0; + uint32_t nalsize = 0; i = next_avc; for (j = 0; j < p->nal_length_size; j++) nalsize = (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); + if (!nalsize || nalsize > buf_size - i) { + av_log(logctx, AV_LOG_ERROR, "AVC-parser: nal size %"PRIu32" " + "remaining %d\n", nalsize, buf_size - i); return buf_size; } next_avc = i + nalsize;
Use an uint32_t for the NAL unit size of an AVC H.264 NAL unit instead of an int as a left shift of a signed value is undefined behaviour if the result doesn't fit into the target type. Also make the log message never output negative lengths. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com> --- libavcodec/h264_parser.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)