From: Mark Andrews <marka@isc.org>
Date: Thu, 30 Jan 2020 07:55:36 +0000 (+1100)
Subject: skip if first is NULL
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fe745d238d8c218dc973f64716863387e341af47;p=thirdparty%2Fbind9.git

skip if first is NULL
---

diff --git a/lib/dns/zoneverify.c b/lib/dns/zoneverify.c
index c19367b0a0e..7a240ff74a6 100644
--- a/lib/dns/zoneverify.c
+++ b/lib/dns/zoneverify.c
@@ -1215,15 +1215,15 @@ verify_nsec3_chains(const vctx_t *vctx, isc_mem_t *mctx) {
 			result = ISC_R_FAILURE;
 		}
 		if (first == NULL || newchain(first, e)) {
-			if (prev != NULL) {
-				if (!checknext(vctx, prev, first)) {
-					result = ISC_R_FAILURE;
-				}
-				if (prev != first) {
-					free_element(mctx, prev);
-				}
-			}
 			if (first != NULL) {
+				if (prev != NULL) {
+					if (!checknext(vctx, prev, first)) {
+						result = ISC_R_FAILURE;
+					}
+					if (prev != first) {
+						free_element(mctx, prev);
+					}
+				}
 				free_element(mctx, first);
 			}
 			prev = first = e;