diff --git a/lib/libc/net/ns_addr.c b/lib/libc/net/ns_addr.c
index 553d31ecdb98..f26ed919df8b 100644
--- a/lib/libc/net/ns_addr.c
+++ b/lib/libc/net/ns_addr.c
@@ -105,7 +105,6 @@ Field(buf, out, len)
 	register char *bp = buf;
 	int i, ibase, base16 = 0, base10 = 0, clen = 0;
 	int hb[6], *hp;
-	char *fmt;
 
 	/*
 	 * first try 2-273#2-852-151-014#socket
@@ -173,13 +172,11 @@ Field(buf, out, len)
 		*--bp = 0; /* Ends Loop */
 	}
 	if (base16) {
-		fmt = "%3x";
 		ibase = 4096;
 	} else if (base10 == 0 && *buf == '0') {
-		fmt = "%3o";
 		ibase = 512;
 	} else {
-		fmt = "%3d";
+		base10 = 1;
 		ibase = 1000;
 	}
 
@@ -190,13 +187,19 @@ Field(buf, out, len)
 	bp = clen + buf - 3;
 	hp = hb + i - 1;
 
-	while (hp > hb) {
-		(void)sscanf(bp, fmt, hp);
-		bp[0] = 0;
-		hp--;
-		bp -= 3;
+	while (hp >= hb) {
+		if (base16)
+			(void)sscanf(bp, "%3x", hp);
+		else if (base10)
+			(void)sscanf(bp, "%3d", hp);
+		else
+			(void)sscanf(bp, "%3o", hp);
+		if (hp > hb) {
+			bp[0] = 0;
+			hp--;
+			bp -= 3;
+		}
 	}
-	(void)sscanf(buf, fmt, hp);
 	cvtbase((long)ibase, 256, hb, i, out, len);
 }