--- waitpacket.c.orig	Fri Dec 26 15:31:29 2014
+++ waitpacket.c	Sun Dec  4 20:55:11 2016
@@ -375,15 +375,15 @@ int recv_tcp(void *packet, size_t size)
 			goto out;
 
 		flags[0] = '\0';
-		if (tcp.th_flags & TH_RST)  strcat(flags, "R");
-		if (tcp.th_flags & TH_SYN)  strcat(flags, "S");
-		if (tcp.th_flags & TH_ACK)  strcat(flags, "A");
-		if (tcp.th_flags & TH_FIN)  strcat(flags, "F");
-		if (tcp.th_flags & TH_PUSH) strcat(flags, "P");
-		if (tcp.th_flags & TH_URG)  strcat(flags, "U");
-		if (tcp.th_flags & TH_X)    strcat(flags, "X");
-		if (tcp.th_flags & TH_Y)    strcat(flags, "Y");
-		if (flags[0] == '\0')    strcat(flags, "none");
+		if (tcp.th_flags & TH_RST)  strlcat(flags, "R", sizeof(flags));
+		if (tcp.th_flags & TH_SYN)  strlcat(flags, "S", sizeof(flags));
+		if (tcp.th_flags & TH_ACK)  strlcat(flags, "A", sizeof(flags));
+		if (tcp.th_flags & TH_FIN)  strlcat(flags, "F", sizeof(flags));
+		if (tcp.th_flags & TH_PUSH) strlcat(flags, "P", sizeof(flags));
+		if (tcp.th_flags & TH_URG)  strlcat(flags, "U", sizeof(flags));
+		if (tcp.th_flags & TH_X)    strlcat(flags, "X", sizeof(flags));
+		if (tcp.th_flags & TH_Y)    strlcat(flags, "Y", sizeof(flags));
+		if (flags[0] == '\0')    strlcat(flags, "none", sizeof(flags));
 
 		log_ip(status, sequence);
 		printf("sport=%d flags=%s seq=%d win=%d rtt=%.1f ms\n",