If a FLAC track uses an unconventional channel layout, the Matroska muxer adds a WAVEFORMATEXTENSIBLE_CHANNEL_MASK VorbisComment to the CodecPrivate to preserve this information. And given that FLAC uses 24bit length fields, the muxer checks if the length is more than this and errors out if it is.
Yet this can never happen, because we create the AVDictionary that is the source for the VorbisComment. It only contains exactly one entry that can't grow infinitely large (in fact, the length of the VorbisComment is <= 4 + 33 + 1 + 18 + strlen(LIBAVFORMAT_IDENT)). So we can simply assert the size to be < (1 << 24) - 4. Signed-off-by: Andreas Rheinhardt <andreas.rheinha...@gmail.com> --- libavformat/matroskaenc.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c index dd77ae64bc..018108b96b 100644 --- a/libavformat/matroskaenc.c +++ b/libavformat/matroskaenc.c @@ -631,10 +631,7 @@ static int put_flac_codecpriv(AVFormatContext *s, AVIOContext *pb, av_dict_set(&dict, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", buf, 0); len = ff_vorbiscomment_length(dict, vendor, NULL, 0); - if (len >= (1 << 24) - 4) { - av_dict_free(&dict); - return AVERROR(EINVAL); - } + av_assert1(len < (1 << 24) - 4); data = av_malloc(len + 4); if (!data) { -- 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".