[MPlayer-dev-eng] [PATCH] Fix uninitialized memory read in vd_ffmpeg.c

[Ivan Kalvachev]

On 3/9/11, Tobias Diedrich <ranma at tdiedrich.de> wrote:
> Reimar Döffinger wrote:
>> Required padding is 32 bytes, so this will not use uninitialized data
>> (unless len is 0 and data NULL I guess -  seems like that has never
>> happened
>> so far though).
>> Since in addition this change means you can no longer debug packages
>> shorter
>> than 16 bytes I'm rather against it.
>
> How about this?
>
> Index: mplayer-svn-vanilla/libmpcodecs/vd_ffmpeg.c
> ===================================================================
> --- mplayer-svn-vanilla.orig/libmpcodecs/vd_ffmpeg.c	2011-02-10
> 21:44:56.791660244 +0100
> +++ mplayer-svn-vanilla/libmpcodecs/vd_ffmpeg.c	2011-03-09
> 22:25:17.415539937 +0100
> @@ -828,8 +828,14 @@
>
>      avctx->hurry_up=(flags&3)?((flags&2)?2:1):0;
>
> -    mp_msg(MSGT_DECVIDEO, MSGL_DBG2, "vd_ffmpeg data: %04x, %04x, %04x,
> %04x\n",
> -           ((int *)data)[0], ((int *)data)[1], ((int *)data)[2], ((int
> *)data)[3]);
> +    if (mp_msg_test(MSGT_DECVIDEO, MSGL_DBG2)) {
> +        int buf[4] = { 0, 0, 0, 0 };
> +        memcpy(buf, data, len > sizeof(buf) ? sizeof(buf) : len);
> +        mp_msg(MSGT_DECVIDEO, MSGL_DBG2,
> +               "vd_ffmpeg data: %04x, %04x, %04x, %04x\n",
> +               buf[0], buf[1], buf[2], buf[3]);
> +    }
> +
>      av_init_packet(&pkt);
>      pkt.data = data;
>      pkt.size = len;

Is there some reason to output it as 32bit numbers?
If I understand correctly it holds bitstream data.
It would be much simpler if it is output as bytes.