[FFmpeg-devel] [PATCH] Add support for large boxes(>32 bit)

[Philip Langdale]

On 2015-05-20 13:13, Niklesh Lalwani wrote:
> From: Niklesh <niklesh.lalwani at iitb.ac.in>
> 
> Signed-off-by: Niklesh <niklesh.lalwani at iitb.ac.in>
> ---
>  libavcodec/movtextdec.c | 20 +++++++++++++++++---
>  1 file changed, 17 insertions(+), 3 deletions(-)
> 
> diff --git a/libavcodec/movtextdec.c b/libavcodec/movtextdec.c
> index 53ffef0..6ff02b3 100644
> --- a/libavcodec/movtextdec.c
> +++ b/libavcodec/movtextdec.c
> @@ -96,7 +96,8 @@ static int mov_text_decode_frame(AVCodecContext 
> *avctx,
>      char *ptr = avpkt->data;
>      char *end;
>      //char *ptr_temp;
> -    int text_length, tsmb_type, style_entries, tsmb_size, tracksize;
> +    int text_length, tsmb_type, style_entries;
> +    uint64_t tsmb_size, tracksize;
>      int **style_start = {0,};
>      int **style_end = {0,};
>      int **style_flags = {0,};
> @@ -147,17 +148,30 @@ static int mov_text_decode_frame(AVCodecContext 
> *avctx,
>              tsmb_type = AV_RB32(tsmb);
>              tsmb += 4;
> 
> +            if (tsmb_size == 1) {
> +                if (tracksize + 16 > avpkt->size)
> +                    break;
> +                tsmb_size = AV_RB64(tsmb);
> +                tsmb += 8;
> +            }
> +
>              if (tracksize + tsmb_size > avpkt->size)
>                  break;
> 
>              if (tsmb_type == MKBETAG('s','t','y','l')) {
> -                if (tracksize + 10 > avpkt->size)
> +                if (tsmb_size > 0xFFFFFFFF) {
> +                    if (tracksize + 18 > avpkt->size)
> +                        break;
> +                } else if (tracksize + 10 > avpkt->size)
>                      break;

I would use a variable for the 10/18 so you don't have to duplicate the 
logic.

>                  style_entries = AV_RB16(tsmb);
>                  tsmb += 2;
> 
>                  // A single style record is of length 12 bytes.
> -                if (tracksize + 10 + style_entries * 12 > avpkt->size)
> +                if (tsmb_size > 0xFFFFFFFF) {
> +                    if (tracksize + 18 + style_entries * 12 > 
> avpkt->size)
> +                        break;
> +                } else if (tracksize + 10 + style_entries * 12 > 
> avpkt->size)
>                      break;
> 
>                  for(i = 0; i < style_entries; i++) {

-- 
--phil