diff --git a/hw/rtl8139.c b/hw/rtl8139.c
index eb22d04..8128b64 100644
--- a/hw/rtl8139.c
+++ b/hw/rtl8139.c
@@ -1783,7 +1783,7 @@
         if (iov) {
             buf2_size = iov_size(iov, 3);
             buf2 = g_malloc(buf2_size);
-            iov_to_buf(iov, 3, buf2, 0, buf2_size);
+            iov_to_buf(iov, 3, 0, buf2, buf2_size);
             buf = buf2;
         }