--- ntp-4.0.99k/ntpd/ntp_control.c~	Sat Jul 15 17:46:05 2000
+++ ntp-4.0.99k/ntpd/ntp_control.c	Thu Apr  5 14:02:43 2001
@@ -1821,9 +1821,18 @@
 					while (cp < reqend &&
 					    isspace((int)*cp))
 						cp++;
-					while (cp < reqend && *cp !=
-					    ',')
-						*tp++ = *cp++;
+					while (cp < reqend && *cp != ',') {
+					    *tp++ = *cp++;
+					    if (tp > buf + sizeof(buf)) {
+						msyslog(LOG_WARNING, "Attempted \"ntpdx\" exploit from IP %d.%d.%d.%d:%d (possibly spoofed)\n", 
+							(ntohl(rmt_addr->sin_addr.s_addr) >> 24) & 0xff,
+							(ntohl(rmt_addr->sin_addr.s_addr) >> 16) & 0xff,
+							(ntohl(rmt_addr->sin_addr.s_addr) >> 8) & 0xff,
+							(ntohl(rmt_addr->sin_addr.s_addr) >> 0) & 0xff,
+							ntohs(rmt_addr->sin_port));
+						return 0;
+					    }
+					}
 					if (cp < reqend)
 						cp++;
 					*tp = '\0';