static int dv_extract_audio_info(DVDemuxContext* c, uint8_t* frame)
{
    const uint8_t* as_pack;
    int freq, stype, smpls, quant, i, ach;

    as_pack = dv_extract_pack(frame, dv_audio_source);
    if (!as_pack || !c->sys) {    /* No audio ? */
        c->ach = 0;
        return 0;
    }

    smpls =  as_pack[1] & 0x3f;       /* samples in this frame - min. samples */
    freq  = (as_pack[4] >> 3) & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */
    stype = (as_pack[3] & 0x1f);      /* 0 - 2CH, 2 - 4CH, 3 - 8CH */
    quant =  as_pack[4] & 0x07;       /* 0 - 16bit linear, 1 - 12bit nonlinear */

    if (stype > 3) {
        av_log(c->fctx, AV_LOG_ERROR, "stype %d is invalid\n", stype);
        c->ach = 0;
        return 0;
    }

    /* note: ach counts PAIRS of channels (i.e. stereo channels) */
    ach = ((int[4]){  1,  0,  2,  4})[stype];
    if (ach == 1 && quant && freq == 2)
        ach = 2;

    /* Dynamic handling of the audio streams in DV */
    for (i = 0; i < ach; i++) {
       if (!c->ast[i]) {
           c->ast[i] = avformat_new_stream(c->fctx, NULL);
           if (!c->ast[i])
               break;
           avpriv_set_pts_info(c->ast[i], 64, 1, 30000);
           c->ast[i]->codec->codec_type = AVMEDIA_TYPE_AUDIO;
           c->ast[i]->codec->codec_id   = CODEC_ID_PCM_S16LE;

           av_init_packet(&c->audio_pkt[i]);
           c->audio_pkt[i].size         = 0;
           c->audio_pkt[i].data         = c->audio_buf[i];
           c->audio_pkt[i].stream_index = c->ast[i]->index;
           c->audio_pkt[i].flags       |= AV_PKT_FLAG_KEY;
       }
       c->ast[i]->codec->sample_rate = dv_audio_frequency[freq];
       c->ast[i]->codec->channels    = 2;
       c->ast[i]->codec->bit_rate    = 2 * dv_audio_frequency[freq] * 16;
       c->ast[i]->start_time         = 0;
    }
    c->ach = i;

    return (c->sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.