From: Mark Andrews <marka@isc.org>
Date: Wed, 25 Mar 2026 05:13:16 +0000 (+1100)
Subject: Allow the dns_rdata_in_apl structure to be walked twice
X-Git-Tag: v9.21.21~8^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f2fd54f4b2a14ab0a9c9eb18b1ddf913e3b29d12;p=thirdparty%2Fbind9.git

Allow the dns_rdata_in_apl structure to be walked twice

The offset value should be set prior to calculating the length.
---

diff --git a/lib/dns/rdata/in_1/apl_42.c b/lib/dns/rdata/in_1/apl_42.c
index ee33fa5c573..ba0d3d041b0 100644
--- a/lib/dns/rdata/in_1/apl_42.c
+++ b/lib/dns/rdata/in_1/apl_42.c
@@ -331,6 +331,8 @@ dns_rdata_apl_first(dns_rdata_in_apl_t *apl) {
 		return ISC_R_NOMORE;
 	}
 
+	apl->offset = 0;
+
 	/*
 	 * Sanity check data.
 	 */
@@ -338,7 +340,6 @@ dns_rdata_apl_first(dns_rdata_in_apl_t *apl) {
 	length = apl->apl[apl->offset + 3] & 0x7f;
 	INSIST(4 + length <= apl->apl_len);
 
-	apl->offset = 0;
 	return ISC_R_SUCCESS;
 }