The hevc_mp4toannexb bsf does not explicitly check whether a NAL unit is so big that it extends beyond the end of the input packet; it does so only implicitly by using the checked version of the bytestream2 API. But this has downsides compared to real checks: It can lead to huge allocations (up to 2GiB) even when the input packet is just a few bytes. And furthermore it leads to uninitialized data being output. So add a check to error out early if it happens.
Also check directly whether there is enough data for the length field. Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> --- libavcodec/hevc_mp4toannexb_bsf.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/libavcodec/hevc_mp4toannexb_bsf.c b/libavcodec/hevc_mp4toannexb_bsf.c index a880d9ba9a..ba1deb2848 100644 --- a/libavcodec/hevc_mp4toannexb_bsf.c +++ b/libavcodec/hevc_mp4toannexb_bsf.c @@ -142,10 +142,14 @@ static int hevc_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out) int nalu_type; int is_irap, add_extradata, extra_size, prev_size; + if (bytestream2_get_bytes_left(&gb) < s->length_size) { + ret = AVERROR_INVALIDDATA; + goto fail; + } for (i = 0; i < s->length_size; i++) nalu_size = (nalu_size << 8) | bytestream2_get_byte(&gb); - if (nalu_size < 2) { + if (nalu_size < 2 || nalu_size > bytestream2_get_bytes_left(&gb)) { ret = AVERROR_INVALIDDATA; goto fail; } -- 2.20.1 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".