diff --git a/lib/cryptodev/rte_crypto_sym.h b/lib/cryptodev/rte_crypto_sym.h
index c907b1646d..daa090b978 100644
--- a/lib/cryptodev/rte_crypto_sym.h
+++ b/lib/cryptodev/rte_crypto_sym.h
@@ -990,6 +990,7 @@ rte_crypto_mbuf_to_vec(const struct rte_mbuf *mb, uint32_t ofs, uint32_t len,
 			/* whole requested data is completed */
 			vec[i].len = left;
 			left = 0;
+			i++;
 			break;
 		}
 
@@ -999,7 +1000,7 @@ rte_crypto_mbuf_to_vec(const struct rte_mbuf *mb, uint32_t ofs, uint32_t len,
 	}
 
 	RTE_ASSERT(left == 0);
-	return i + 1;
+	return i;
 }