diff --git a/util/iov.c b/util/iov.c
index 003fcce66f..74e6ca8ed7 100644
--- a/util/iov.c
+++ b/util/iov.c
@@ -247,7 +247,8 @@ unsigned iov_copy(struct iovec *dst_iov, unsigned int dst_iov_cnt,
 {
     size_t len;
     unsigned int i, j;
-    for (i = 0, j = 0; i < iov_cnt && j < dst_iov_cnt && bytes; i++) {
+    for (i = 0, j = 0;
+         i < iov_cnt && j < dst_iov_cnt && (offset || bytes); i++) {
         if (offset >= iov[i].iov_len) {
             offset -= iov[i].iov_len;
             continue;