ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinha...@outlook.com> | Tue May 26 20:26:28 2020 +0200| [c83a7dd25fdf9636e7e5da3fad5e0d82035b9c86] | committer: Andreas Rheinhardt
avcodec/h264_parser: Fix undefined left shift 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. 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 Reviewed-by: Michael Niedermayer <mich...@niedermayer.cc> Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@outlook.com> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=c83a7dd25fdf9636e7e5da3fad5e0d82035b9c86 --- libavcodec/h264_parser.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/libavcodec/h264_parser.c b/libavcodec/h264_parser.c index d3c56cc188..01ea016409 100644 --- a/libavcodec/h264_parser.c +++ b/libavcodec/h264_parser.c @@ -83,12 +83,13 @@ 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; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
