[FFmpeg-devel] [PATCH] lavf/id3v2: fail read_apic on EOF reading mimetype

[Tomas Härdin]

ons 2018-12-12 klockan 18:59 -0800 skrev chcunningham:
> avio_read may return EOF, leaving the mimetype array unitialized. fail
> early when this occurs to avoid using the array in an unitialized state.
> ---
>  libavformat/id3v2.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
> index f7de26a1d8..7c4d1f8677 100644
> --- a/libavformat/id3v2.c
> +++ b/libavformat/id3v2.c
> @@ -612,7 +612,9 @@ static void read_apic(AVFormatContext *s, AVIOContext *pb, int taglen,
>      if (isv34) {
>          taglen -= avio_get_str(pb, taglen, mimetype, sizeof(mimetype));
>      } else {
> -        avio_read(pb, mimetype, 3);
> +        if (avio_read(pb, mimetype, 3) < 0)
> +            goto fail;
> +
>          mimetype[3] = 0;
>          taglen    -= 3;
>      }

Yet another problem that could have been caught by static analysis..
Wouldn't it be better to always leave the array in a valid state?

/Tomas