avcodec/mpc8: check for overread first

[ffmpeg] / libavcodec / h264_slice.c

diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c
index aad54845888d021ad062ce41fa77af42a1115910..90e05ed8f1021682bb985981177345d42c61b5c1 100644 (file)
--- a/libavcodec/h264_slice.c
+++ b/libavcodec/h264_slice.c
@@ -1571,6 +1571,12 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl,
                  * one except for reference purposes. */
                 h->first_field = 1;
                 h->cur_pic_ptr = NULL;
+            } else if (h->cur_pic_ptr->reference & DELAYED_PIC_REF) {
+                /* This frame was already output, we cannot draw into it
+                 * anymore.
+                 */
+                h->first_field = 1;
+                h->cur_pic_ptr = NULL;
             } else {
                 /* Second field in complementary pair */
                 h->first_field = 0;
@@ -1601,8 +1607,10 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl,
             (h->mb_height * h->mb_stride - 1) * sizeof(*h->slice_table));
     }
 
-    ff_h264_init_poc(h->cur_pic_ptr->field_poc, &h->cur_pic_ptr->poc,
+    ret = ff_h264_init_poc(h->cur_pic_ptr->field_poc, &h->cur_pic_ptr->poc,
                      h->ps.sps, &h->poc, h->picture_structure, nal->ref_idc);
+    if (ret < 0)
+        return ret;
 
     memcpy(h->mmco, sl->mmco, sl->nb_mmco * sizeof(*h->mmco));
     h->nb_mmco = sl->nb_mmco;