From fedfd48a089450a8358742084c38fcfa443aeb9d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@sury.org>
Date: Thu, 3 Oct 2019 10:16:03 +0200
Subject: [PATCH] lib/dns/zone.c: Fix invalid order of DbC checks that could
 cause dereference before NULL check

---
 lib/dns/zone.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index be0865c891..c568e6a446 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -5507,8 +5507,8 @@ zone_iattach(dns_zone_t *source, dns_zone_t **target) {
 	/*
 	 * 'source' locked by caller.
 	 */
-	REQUIRE(LOCKED_ZONE(source));
 	REQUIRE(DNS_ZONE_VALID(source));
+	REQUIRE(LOCKED_ZONE(source));
 	REQUIRE(target != NULL && *target == NULL);
 	INSIST(source->irefs + isc_refcount_current(&source->erefs) > 0);
 	source->irefs++;