Fix TCPDNS socket closing issues

diff --git a/lib/isc/netmgr/tcpdns.c b/lib/isc/netmgr/tcpdns.c
index fecfb47babe1ea696ffe3b26e8f31b66454d64d5..379ff99bf3a81feb447090df62da1be2af275e48 100644 (file)
--- a/lib/isc/netmgr/tcpdns.c
+++ b/lib/isc/netmgr/tcpdns.c
@@ -43,6 +43,9 @@ dnslisten_readcb(isc_nmhandle_t *handle, isc_region_t *region, void *arg);
 static void
 resume_processing(void *arg);
 
+static void
+tcpdns_close_direct(isc_nmsocket_t *sock);
+
 static inline size_t
 dnslen(unsigned char *base) {
        return ((base[0] << 8) + (base[1]));
@@ -79,7 +82,6 @@ static void
 timer_close_cb(uv_handle_t *handle) {
        isc_nmsocket_t *sock = (isc_nmsocket_t *)uv_handle_get_data(handle);
        INSIST(VALID_NMSOCK(sock));
-       atomic_store(&sock->closed, true);
        isc_nmsocket_detach(&sock);
 }
 
@@ -90,9 +92,7 @@ dnstcp_readtimeout(uv_timer_t *timer) {
 
        REQUIRE(VALID_NMSOCK(sock));
        REQUIRE(sock->tid == isc_nm_tid());
-
-       isc_nmsocket_detach(&sock->outer);
-       uv_close((uv_handle_t *)&sock->timer, timer_close_cb);
+       tcpdns_close_direct(sock);
 }
 
 /*
@@ -492,18 +492,29 @@ isc__nm_tcpdns_send(isc_nmhandle_t *handle, isc_region_t *region,
 static void
 tcpdns_close_direct(isc_nmsocket_t *sock) {
        REQUIRE(sock->tid == isc_nm_tid());
-       if (sock->outer != NULL) {
-               sock->outer->rcb.recv = NULL;
-               isc_nmsocket_detach(&sock->outer);
-       }
-       if (sock->listener != NULL) {
-               isc_nmsocket_detach(&sock->listener);
-       }
        /* We don't need atomics here, it's all in single network thread */
        if (sock->timer_initialized) {
+               /*
+                * We need to fire the timer callback to clean it up,
+                * it will then call us again (via detach) so that we
+                * can finally close the socket.
+                */
                sock->timer_initialized = false;
                uv_timer_stop(&sock->timer);
                uv_close((uv_handle_t *)&sock->timer, timer_close_cb);
+       } else {
+               /*
+                * At this point we're certain that there are no external
+                * references, we can close everything.
+                */
+               if (sock->outer != NULL) {
+                       sock->outer->rcb.recv = NULL;
+                       isc_nmsocket_detach(&sock->outer);
+               }
+               if (sock->listener != NULL) {
+                       isc_nmsocket_detach(&sock->listener);
+               }
+               atomic_store(&sock->closed, true);
        }
 }