RepoMirrors/ffmpeg
1
0
Fork 0
mirror of https://git.ffmpeg.org/ffmpeg.git synced 2024-12-27 09:52:17 +00:00
Code Issues Projects Releases Wiki Activity

avformat/matroskaenc: Replace impossible condition with assert

Browse Source 
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.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2020-04-28 02:24:16 +02:00
parent d13feae0f8
commit ca0a38f2f7
1 changed files with 1 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
libavformat/matroskaenc.c
View File

@ -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) {