libavcodec/h264.c:6539: error: Buffer Overrun L1
  Offset: [2, 21] (⇐ [2, 20] + [0, 1]) Size: 2.

libavcodec/h264.c:6538:26: <Offset trace>
6536.                     int v = 0;
6537. 
6538.                     for( l = 0; !v && l < 1 + (h->slice_type_nos == FF_B_TYPE); l++ ) {
                               ^
6539.                         v |= ref2frm[l][h->ref_cache[l][b_idx]] != ref2frmn[l][h->ref_cache[l][bn_idx]] ||
6540.                              FFABS( h->mv_cache[l][b_idx][0] - h->mv_cache[l][bn_idx][0] ) >= 4 ||

libavcodec/h264.c:6538:26: Assignment
6536.                     int v = 0;
6537. 
6538.                     for( l = 0; !v && l < 1 + (h->slice_type_nos == FF_B_TYPE); l++ ) {
                               ^
6539.                         v |= ref2frm[l][h->ref_cache[l][b_idx]] != ref2frmn[l][h->ref_cache[l][bn_idx]] ||
6540.                              FFABS( h->mv_cache[l][b_idx][0] - h->mv_cache[l][bn_idx][0] ) >= 4 ||

libavcodec/h264.c:6306:1: <Length trace>
6304. }
6305. 
6306. static void filter_mb( H264Context *h, int mb_x, int mb_y, uint8_t *img_y, uint8_t *img_cb, uint8_t *img_cr, unsigned int linesize, unsigned int uvlinesize) {
      ^
6307.     MpegEncContext * const s = &h->s;
6308.     const int mb_xy= mb_x + mb_y*s->mb_stride;

libavcodec/h264.c:6306:1: Parameter `h->ref2frm[*][*]`
6304. }
6305. 
6306. static void filter_mb( H264Context *h, int mb_x, int mb_y, uint8_t *img_y, uint8_t *img_cb, uint8_t *img_cr, unsigned int linesize, unsigned int uvlinesize) {
      ^
6307.     MpegEncContext * const s = &h->s;
6308.     const int mb_xy= mb_x + mb_y*s->mb_stride;

libavcodec/h264.c:6429:9: Assignment
6427.         const int mbm_xy = dir == 0 ? mb_xy -1 : h->top_mb_xy;
6428.         const int mbm_type = s->current_picture.mb_type[mbm_xy];
6429.         int (*ref2frm) [64] = h->ref2frm[ h->slice_num          &(MAX_SLICES-1) ][0] + (MB_MBAFF ? 20 : 2);
              ^
6430.         int (*ref2frmm)[64] = h->ref2frm[ h->slice_table[mbm_xy]&(MAX_SLICES-1) ][0] + (MB_MBAFF ? 20 : 2);
6431.         int start = h->slice_table[mbm_xy] == 0xFFFF ? 1 : 0;

libavcodec/h264.c:6539:30: Array access: Offset: [2, 21] (⇐ [2, 20] + [0, 1]) Size: 2
6537. 
6538.                     for( l = 0; !v && l < 1 + (h->slice_type_nos == FF_B_TYPE); l++ ) {
6539.                         v |= ref2frm[l][h->ref_cache[l][b_idx]] != ref2frmn[l][h->ref_cache[l][bn_idx]] ||
                                   ^
6540.                              FFABS( h->mv_cache[l][b_idx][0] - h->mv_cache[l][bn_idx][0] ) >= 4 ||
6541.                              FFABS( h->mv_cache[l][b_idx][1] - h->mv_cache[l][bn_idx][1] ) >= mvy_limit;
