diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 78527270d1..2c213b394c 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -1729,6 +1729,7 @@ static int decode_frame(AVCodecContext *avctx, void *data,
     avctx->execute2(avctx, decode_block, s->thread_data, NULL, nb_blocks);
 
     // Zero out the end if ymax+1 is not h
+    ptr = picture->data[0] + ((s->ymax+1) * picture->linesize[0]);
     for (y = s->ymax + 1; y < avctx->height; y++) {
         memset(ptr, 0, out_line_size);
         ptr += picture->linesize[0];