--- embedaddon/mtr/ui/asn.c	2021/03/17 00:07:30	1.1.1.2
+++ embedaddon/mtr/ui/asn.c	2023/09/27 11:18:58	1.1.1.3
@@ -207,11 +207,11 @@ static void reverse_host6(
 {
     int i;
     char *b = buff;
-    for (i = (sizeof(*addr) / 2 - 1); i >= 0; i--, b += 4)      /* 64b portion */
+    // We need to process the top 64 bits, or 8 bytes.
+    for (i = 8-1; i >= 0; i--, b += 4, buff_length -= 4)
         snprintf(b, buff_length,
                  "%x.%x.", addr->s6_addr[i] & 0xf, addr->s6_addr[i] >> 4);
-
-    buff[strlen(buff) - 1] = '\0';
+    *--b = 0;
 }
 #endif