diff --git a/libavcodec/qpeg.c b/libavcodec/qpeg.c
index 654fd998d6..d4195c5f0b 100644
--- a/libavcodec/qpeg.c
+++ b/libavcodec/qpeg.c
@@ -99,6 +99,8 @@ static void qpeg_decode_intra(QpegContext *qctx, uint8_t *dst,
                 }
             }
         } else {
+            if (bytestream2_get_bytes_left(&qctx->buffer) < copy)
+                copy = bytestream2_get_bytes_left(&qctx->buffer);
             for(i = 0; i < copy; i++) {
                 dst[filled++] = bytestream2_get_byte(&qctx->buffer);
                 if (filled >= width) {