diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 162b3bb252..80117deb8a 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -1789,7 +1789,7 @@ static int decode_frame(AVCodecContext *avctx, void *data,
     if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
         return ret;
 
-    if (bytestream2_get_bytes_left(&s->gb) < nb_blocks * 8)
+    if (bytestream2_get_bytes_left(&s->gb)/8 < nb_blocks)
         return AVERROR_INVALIDDATA;
 
     // check offset table and recreate it if need