From cfc22e53a89ccac4eb04b4f41a93f73e629e80ed Mon Sep 17 00:00:00 2001
From: Evan Hunt <each@isc.org>
Date: Wed, 25 Nov 2009 05:55:32 +0000
Subject: [PATCH] 2789.   [bug]           Fixed an INSIST in dispatch.c [RT
 #20576]

---
 CHANGES            |  2 ++
 lib/dns/dispatch.c | 14 +++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/CHANGES b/CHANGES
index 782a0d893c..363b22820a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,5 @@
+2789.   [bug]           Fixed an INSIST in dispatch.c [RT #20576]
+
 2788.	[bug]		dnssec-signzone could sign with keys that were
 			not requested [RT #20625]
 
diff --git a/lib/dns/dispatch.c b/lib/dns/dispatch.c
index e13230557e..947a48e97f 100644
--- a/lib/dns/dispatch.c
+++ b/lib/dns/dispatch.c
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: dispatch.c,v 1.164 2009/09/01 00:22:26 jinmei Exp $ */
+/* $Id: dispatch.c,v 1.165 2009/11/25 05:55:32 each Exp $ */
 
 /*! \file */
 
@@ -778,6 +778,9 @@ new_portentry(dns_dispatch_t *disp, in_port_t port) {
 	return (portentry);
 }
 
+/*%
+ * The caller must not hold the qid->lock.
+ */
 static void
 deref_portentry(dns_dispatch_t *disp, dispportentry_t **portentryp) {
 	dispportentry_t *portentry = *portentryp;
@@ -785,6 +788,9 @@ deref_portentry(dns_dispatch_t *disp, dispportentry_t **portentryp) {
 	REQUIRE(disp->port_table != NULL);
 	REQUIRE(portentry != NULL && portentry->refs > 0);
 
+	dns_qid_t *qid;
+	qid = DNS_QID(disp);
+	LOCK(&qid->lock);
 	portentry->refs--;
 	if (portentry->refs == 0) {
 		ISC_LIST_UNLINK(disp->port_table[portentry->port %
@@ -794,6 +800,7 @@ deref_portentry(dns_dispatch_t *disp, dispportentry_t **portentryp) {
 	}
 
 	*portentryp = NULL;
+	UNLOCK(&qid->lock);
 }
 
 /*%
@@ -811,8 +818,9 @@ socket_search(dns_qid_t *qid, isc_sockaddr_t *dest, in_port_t port,
 	dispsock = ISC_LIST_HEAD(qid->sock_table[bucket]);
 
 	while (dispsock != NULL) {
-		if (isc_sockaddr_equal(dest, &dispsock->host) &&
-		    dispsock->portentry->port == port)
+                if (dispsock->portentry != NULL &&
+		    dispsock->portentry->port == port &&
+		    isc_sockaddr_equal(dest, &dispsock->host))
 			return (dispsock);
 		dispsock = ISC_LIST_NEXT(dispsock, blink);
 	}