From: Witold Kręcicki <wpk@isc.org>
Date: Thu, 25 Oct 2018 18:49:28 +0000 (+0000)
Subject: Fix a race in RPZ with min-update-interval set to 0
X-Git-Tag: v9.13.4~74^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=faf2c7711aadde2c9bf7a142e7a53fc26236ebae;p=thirdparty%2Fbind9.git

Fix a race in RPZ with min-update-interval set to 0

If another RPZ update is pending when processing the previous one nears
completion and min-update-interval is set to 0, isc_timer_reset() gets
called with 'interval' set to 0, which triggers an assertion failure.
To prevent such a scenario from causing a crash, queue the update event
directly instead of asking the timer thread to do it.
---

diff --git a/CHANGES b/CHANGES
index 323b684e6c4..02e42282a46 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,9 @@
+5069.	[bug]		Fix a hang on in RPZ when named is shutdown during RPZ
+			zone update. [GL !907]
+
+5068.	[bug]		Fix a race in RPZ with min-update-interval set to 0.
+			[GL #643]
+
 5067.	[bug]		Don't minimize qname when sending the query
 			to a forwarder. [GL #361]
 
diff --git a/lib/dns/rpz.c b/lib/dns/rpz.c
index 1f919e12015..fa8b3d4491e 100644
--- a/lib/dns/rpz.c
+++ b/lib/dns/rpz.c
@@ -1802,18 +1802,30 @@ finish_update(dns_rpz_zone_t *rpz) {
 	 * If there's an update pending schedule it
 	 */
 	if (rpz->updatepending == true) {
-		uint64_t defer = rpz->min_update_interval;
-		isc_interval_t interval;
-		dns_name_format(&rpz->origin, dname,
-				DNS_NAME_FORMATSIZE);
-		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
-			      DNS_LOGMODULE_MASTER, ISC_LOG_INFO,
-			      "rpz: %s: new zone version came "
-			      "too soon, deferring update for "
-			      "%" PRIu64 " seconds", dname, defer);
-		isc_interval_set(&interval, (unsigned int)defer, 0);
-		isc_timer_reset(rpz->updatetimer, isc_timertype_once,
-				NULL, &interval, true);
+		if (rpz->min_update_interval > 0) {
+			uint64_t defer = rpz->min_update_interval;
+			isc_interval_t interval;
+			dns_name_format(&rpz->origin, dname,
+					DNS_NAME_FORMATSIZE);
+			isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+				      DNS_LOGMODULE_MASTER, ISC_LOG_INFO,
+				      "rpz: %s: new zone version came "
+				      "too soon, deferring update for "
+				      "%" PRIu64 " seconds", dname, defer);
+			isc_interval_set(&interval, (unsigned int)defer, 0);
+			isc_timer_reset(rpz->updatetimer, isc_timertype_once,
+					NULL, &interval, true);
+		} else {
+			isc_event_t *event;
+			INSIST(!ISC_LINK_LINKED(&rpz->updateevent, ev_link));
+			ISC_EVENT_INIT(&rpz->updateevent,
+				       sizeof(rpz->updateevent), 0, NULL,
+				       DNS_EVENT_RPZUPDATED,
+				       dns_rpz_update_taskaction,
+				       rpz, rpz, NULL, NULL);
+			event = &rpz->updateevent;
+			isc_task_send(rpz->rpzs->updater, &event);
+		}
 	}
 	UNLOCK(&rpz->rpzs->maint_lock);