From: Colin Vidal <colin@isc.org>
Date: Mon, 17 Nov 2025 11:33:48 +0000 (+0100)
Subject: enforces bounds of prefetch statement
X-Git-Tag: v9.21.16~48^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5c038c2fa2c74a07c08d50e621b48fcff9125ad1;p=thirdparty%2Fbind9.git

enforces bounds of prefetch statement

The prefetch statement now enforces its bounds. The configuration
(including `named-checkconf`) now fails if the trigger (first value) is
above 10, or if the eligibility (second optional value) isn't at least
six seconds more than the trigger value.
---

diff --git a/bin/tests/system/checkconf/bad-prefetch1.conf b/bin/tests/system/checkconf/bad-prefetch1.conf
new file mode 100644
index 00000000000..8051c63167a
--- /dev/null
+++ b/bin/tests/system/checkconf/bad-prefetch1.conf
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+options {
+	prefetch 11;
+};
diff --git a/bin/tests/system/checkconf/bad-prefetch2.conf b/bin/tests/system/checkconf/bad-prefetch2.conf
new file mode 100644
index 00000000000..a2419a1d1aa
--- /dev/null
+++ b/bin/tests/system/checkconf/bad-prefetch2.conf
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+options {
+	prefetch 2 7;
+};
diff --git a/bin/tests/system/checkconf/bad-prefetch3.conf b/bin/tests/system/checkconf/bad-prefetch3.conf
new file mode 100644
index 00000000000..adee152be78
--- /dev/null
+++ b/bin/tests/system/checkconf/bad-prefetch3.conf
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+view foo {
+	prefetch 11;
+};
diff --git a/bin/tests/system/checkconf/bad-prefetch4.conf b/bin/tests/system/checkconf/bad-prefetch4.conf
new file mode 100644
index 00000000000..5fc48c077e4
--- /dev/null
+++ b/bin/tests/system/checkconf/bad-prefetch4.conf
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0.  If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+view foo {
+	prefetch 9 13;
+};
diff --git a/lib/isccfg/check.c b/lib/isccfg/check.c
index fb1e1d92b91..f8c16974579 100644
--- a/lib/isccfg/check.c
+++ b/lib/isccfg/check.c
@@ -1999,6 +1999,37 @@ check_options(const cfg_obj_t *options, const cfg_obj_t *config,
 		}
 	}
 
+	obj = NULL;
+	(void)cfg_map_get(options, "prefetch", &obj);
+	if (obj != NULL) {
+		const cfg_obj_t *trigger = cfg_tuple_get(obj, "trigger");
+		const cfg_obj_t *eligible = cfg_tuple_get(obj, "eligible");
+		uint32_t tvalue = cfg_obj_asuint32(trigger);
+
+		if (tvalue > 10) {
+			cfg_obj_log(obj, ISC_LOG_ERROR,
+				    "prefetch '%u' out of range (0..10)",
+				    tvalue);
+			if (result == ISC_R_SUCCESS) {
+				result = ISC_R_RANGE;
+			}
+		}
+
+		if (!cfg_obj_isvoid(eligible)) {
+			uint32_t evalue = cfg_obj_asuint32(eligible);
+			if (evalue < tvalue + 6) {
+				cfg_obj_log(obj, ISC_LOG_ERROR,
+					    "prefetch eligibility '%u' must be "
+					    "at least six seconds longer than "
+					    "the trigger value '%u'",
+					    evalue, tvalue);
+				if (result == ISC_R_SUCCESS) {
+					result = ISC_R_RANGE;
+				}
+			}
+		}
+	}
+
 	if (aclctx != NULL) {
 		cfg_aclconfctx_detach(&aclctx);
 	}
diff --git a/lib/isccfg/namedconf.c b/lib/isccfg/namedconf.c
index 0145f2b4848..e2d5796ed9d 100644
--- a/lib/isccfg/namedconf.c
+++ b/lib/isccfg/namedconf.c
@@ -2237,9 +2237,6 @@ prefetch_merge(cfg_obj_t *effectiveobj, const cfg_obj_t *defaultobj) {
 
 	trigger = (cfg_obj_t *)cfg_tuple_get(effectiveobj, "trigger");
 	INSIST(cfg_obj_isuint32(trigger));
-	if (cfg_obj_asuint32(trigger) > 10) {
-		trigger->value.uint32 = 10;
-	}
 
 	eligible = (cfg_obj_t *)cfg_tuple_get(effectiveobj, "eligible");
 	if (cfg_obj_isvoid(eligible)) {
@@ -2253,9 +2250,6 @@ prefetch_merge(cfg_obj_t *effectiveobj, const cfg_obj_t *defaultobj) {
 	}
 
 	INSIST(cfg_obj_isuint32(eligible));
-	if (cfg_obj_asuint32(eligible) < cfg_obj_asuint32(trigger) + 6) {
-		eligible->value.uint32 = cfg_obj_asuint32(trigger) + 6;
-	}
 }
 
 static void