Index: sys/netinet/tcp_lro.c
===================================================================
--- sys/netinet/tcp_lro.c
+++ sys/netinet/tcp_lro.c
@@ -347,9 +347,13 @@
 	if (ret != 0)
 		goto done;
 
-	ret = ma->m_pkthdr.flowid - mb->m_pkthdr.flowid;
-	if (ret != 0)
+	if (ma->m_pkthdr.flowid > mb->m_pkthdr.flowid) {
+		ret++;
+		goto done;
+	} else if (ma->m_pkthdr.flowid < mb->m_pkthdr.flowid) {
+		ret--;
 		goto done;
+	}
 
 	ret = TCP_LRO_SEQUENCE(ma) - TCP_LRO_SEQUENCE(mb);
 done: