diff --git a/lib/dns/dispatch.c b/lib/dns/dispatch.c
index 4a77b7fe45..6cd2fd7fe3 100644
--- a/lib/dns/dispatch.c
+++ b/lib/dns/dispatch.c
@@ -1045,9 +1045,11 @@ udp_recv(isc_event_t *ev_in, dns_dispatch_t *disp, dispsocket_t *dispsock) {
 	mgr = disp->mgr;
 	qid = mgr->qid;
 
+	LOCK(&disp->mgr->buffer_lock);
 	dispatch_log(disp, LVL(90),
 		     "got packet: requests %d, buffers %d, recvs %d",
 		     disp->requests, disp->mgr->buffers, disp->recv_pending);
+	UNLOCK(&disp->mgr->buffer_lock);
 
 	if (dispsock == NULL && ev->ev_type == ISC_SOCKEVENT_RECVDONE) {
 		/*