From dc71aa898a4d4a56ca9cb60215e9b0907a1518c3 Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Fri, 15 Sep 2017 13:14:16 +1000
Subject: [PATCH] don't use strlcat with non NUL terminated strings
 rt45981_stage3

---
 lib/dns/rcode.c | 8 ++++----
 lib/dns/rdata.c | 4 ++--
 lib/dns/ttl.c   | 2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/lib/dns/rcode.c b/lib/dns/rcode.c
index 8cad290937..aaec1afa1d 100644
--- a/lib/dns/rcode.c
+++ b/lib/dns/rcode.c
@@ -252,8 +252,8 @@ maybe_numeric(unsigned int *valuep, isc_textregion_t *source,
 	 * isc_parse_uint32().	isc_parse_uint32() requires
 	 * null termination, so we must make a copy.
 	 */
-	strlcpy(buffer, source->base,
-		ISC_MIN(source->length + 1, sizeof(buffer)));
+	snprintf(buffer, sizeof(buffer), "%.*s",
+		 (int)source->length, source->base);
 
 	INSIST(buffer[source->length] == '\0');
 
@@ -508,8 +508,8 @@ dns_rdataclass_fromtext(dns_rdataclass_t *classp, isc_textregion_t *source) {
 			 * source->base is not required to be NUL terminated.
 			 * Copy up to remaining bytes and NUL terminate.
 			 */
-			strlcpy(buf, source->base + 5,
-				ISC_MIN(source->length - 5 + 1, sizeof(buf)));
+			snprintf(buf, sizeof(buf), "%.*s",
+				 (int)(source->length - 5), source->base + 5);
 			val = strtoul(buf, &endp, 10);
 			if (*endp == '\0' && val <= 0xffff) {
 				*classp = (dns_rdataclass_t)val;
diff --git a/lib/dns/rdata.c b/lib/dns/rdata.c
index fd55eff695..f1c86e2dbf 100644
--- a/lib/dns/rdata.c
+++ b/lib/dns/rdata.c
@@ -1343,8 +1343,8 @@ dns_rdatatype_fromtext(dns_rdatatype_t *typep, isc_textregion_t *source) {
 		 * source->base is not required to be NUL terminated.
 		 * Copy up to remaining bytes and NUL terminate.
 		 */
-		strlcpy(buf, source->base + 4,
-			ISC_MIN(source->length - 4 + 1, sizeof(buf)));
+		snprintf(buf, sizeof(buf), "%.*s",
+			 (int)(source->length - 4), source->base + 4);
 		val = strtoul(buf, &endp, 10);
 		if (*endp == '\0' && val <= 0xffff) {
 			*typep = (dns_rdatatype_t)val;
diff --git a/lib/dns/ttl.c b/lib/dns/ttl.c
index 1afca6426c..06239c4dd2 100644
--- a/lib/dns/ttl.c
+++ b/lib/dns/ttl.c
@@ -160,7 +160,7 @@ bind_ttl(isc_textregion_t *source, isc_uint32_t *ttl) {
 	if (source->length > sizeof(buf) - 1)
 		return (DNS_R_SYNTAX);
 	/* Copy source->length bytes and NUL terminate. */
-	strlcpy(buf, source->base, ISC_MIN(source->length + 1, sizeof(buf)));
+	snprintf(buf, sizeof(buf), "%.*s", (int)source->length, source->base);
 	s = buf;
 
 	do {