[FFmpeg-devel] [PATCH] dvbsubdec: check against buffer overreads

[Måns Rullgård]

Janne Grunau <janne-ffmpeg at jannau.net> writes:

> Signed-off-by: Janne Grunau <janne-ffmpeg at jannau.net>
> ---
>  libavcodec/dvbsubdec.c |   11 +++++++++--
>  1 files changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/libavcodec/dvbsubdec.c b/libavcodec/dvbsubdec.c
> index 401144f..c06c017 100644
> --- a/libavcodec/dvbsubdec.c
> +++ b/libavcodec/dvbsubdec.c
> @@ -1423,13 +1423,15 @@ static int dvbsub_decode(AVCodecContext *avctx,
>
>  #endif
>
> -    if (buf_size <= 2 || *buf != 0x0f)
> +    if (buf_size <= 6 || *buf != 0x0f) {
> +        av_dlog(avctx, "incomplete or broken packet");
>          return -1;
> +    }
>
>      p = buf;
>      p_end = buf + buf_size;
>
> -    while (p < p_end && *p == 0x0f) {
> +    while (p_end - p < 6 && *p == 0x0f) {

Err, > 6, no?

-- 
M?ns Rullg?rd
mans at mansr.com