diff --git a/src/knot/server/xfr-handler.c b/src/knot/server/xfr-handler.c
index 01ce1bc2056d9a7392a3d3e13c5faac1f769e210..39ffeebac14f2600d957c2d9df5331155b917ec5 100644
--- a/src/knot/server/xfr-handler.c
+++ b/src/knot/server/xfr-handler.c
@@ -143,11 +143,15 @@ static knot_ns_xfr_t *xfr_handler_task(xfrworker_t *w, int fd)
static int xfr_udp_timeout(knot_ns_xfr_t *data)
{
/* Close socket. */
+ rcu_read_lock();
knot_zone_t *z = data->zone;
if (z && knot_zone_get_contents(z) && knot_zone_data(z)) {
- log_zone_info("%s Failed, timeout exceeded.\n",
- data->msgpref);
+ if (!(knot_zone_flags(z) & KNOT_ZONE_DISCARDED)) {
+ log_zone_info("%s Failed, timeout exceeded.\n",
+ data->msgpref);
+ }
}
+ rcu_read_unlock();
/* Invalidate pending query. */
xfr_free_task(data);
@@ -165,6 +169,13 @@ static int xfr_udp_timeout(knot_ns_xfr_t *data)
*/
static int xfr_process_udp_resp(xfrworker_t *w, int fd, knot_ns_xfr_t *data)
{
+ /* Check if zone is valid. */
+ rcu_read_lock();
+ if (knot_zone_flags(data->zone) & KNOT_ZONE_DISCARDED) {
+ return KNOTD_ECONNREFUSED;
+ }
+ rcu_read_unlock();
+
/* Receive msg. */
ssize_t n = recvfrom(data->session, data->wire, data->wire_size, 0, data->addr.ptr, &data->addr.len);
size_t resp_len = data->wire_size;
@@ -611,8 +622,14 @@ int xfr_process_event(xfrworker_t *w, int fd, knot_ns_xfr_t *data, uint8_t *buf,
/* Read DNS/TCP packet. */
int ret = 0;
int rcvd = tcp_recv(fd, buf, buflen, 0);
+
+ /* Raise read-lock and check if zone is still valid. */
+ rcu_read_lock();
+ int zone_discarded = (knot_zone_flags(zone) & KNOT_ZONE_DISCARDED);
+
+ /* Handle incoming packet. */
data->wire_size = rcvd;
- if (rcvd <= 0) {
+ if (rcvd <= 0 || zone_discarded) {
data->wire_size = 0;
ret = KNOT_ECONN;
} else {
@@ -673,12 +690,14 @@ int xfr_process_event(xfrworker_t *w, int fd, knot_ns_xfr_t *data, uint8_t *buf,
}
/* Handle errors. */
- if (ret == KNOT_ENOXFR) {
- log_server_warning("%s Finished, %s\n",
- data->msgpref, knot_strerror(ret));
- } else if (ret < 0) {
- log_server_error("%s %s\n",
- data->msgpref, knot_strerror(ret));
+ if (!zone_discarded) {
+ if (ret == KNOT_ENOXFR) {
+ log_server_warning("%s Finished, %s\n",
+ data->msgpref, knot_strerror(ret));
+ } else if (ret < 0) {
+ log_server_error("%s %s\n",
+ data->msgpref, knot_strerror(ret));
+ }
}
/* Check finished zone. */
@@ -698,13 +717,11 @@ int xfr_process_event(xfrworker_t *w, int fd, knot_ns_xfr_t *data, uint8_t *buf,
knot_zone_t *zone = (knot_zone_t *)data->zone;
zonedata_t *zd = (zonedata_t *)knot_zone_data(zone);
- /* Only for successful xfers. */
- if (ret > 0) {
+ /* Only for successful xfers on non-discarded zones. */
+ if (ret > 0 && !zone_discarded) {
ret = xfr_xfrin_finalize(w, data);
/* AXFR bootstrap timeout. */
- rcu_read_lock();
- /*! \todo #1976 Do not reschedule if zone is being discarded. */
if (ret != KNOTD_EOK && !knot_zone_contents(zone)) {
/* Schedule request (60 - 90s random delay). */
int tmr_s = AXFR_BOOTSTRAP_RETRY;
@@ -718,8 +735,6 @@ int xfr_process_event(xfrworker_t *w, int fd, knot_ns_xfr_t *data, uint8_t *buf,
/* Update timers. */
server_t *server = (server_t *)knot_ns_get_data(w->ns);
zones_timers_update(zone, zd->conf, server->sched);
- rcu_read_unlock();
-
} else {
/* Cleanup */
xfr_xfrin_cleanup(w, data);
@@ -740,6 +755,8 @@ int xfr_process_event(xfrworker_t *w, int fd, knot_ns_xfr_t *data, uint8_t *buf,
/* Disconnect. */
result = KNOTD_ECONNREFUSED; /* Make it disconnect. */
}
+
+ rcu_read_unlock();
return result;
}
@@ -1418,6 +1435,14 @@ static int xfr_process_request(xfrworker_t *w, uint8_t *buf, size_t buflen)
}
conf_read_lock();
+
+ /* Check if the zone is not discarded. */
+ if (knot_zone_flags(xfr.zone) & KNOT_ZONE_DISCARDED) {
+ xfr_request_deinit(&xfr);
+ knot_zone_release(xfr.zone);
+ conf_read_unlock();
+ return KNOTD_EOK;
+ }
/* Handle request. */
knot_ns_xfr_t *task = NULL;
@@ -1430,7 +1455,6 @@ static int xfr_process_request(xfrworker_t *w, uint8_t *buf, size_t buflen)
/* Report. */
if (ret != KNOTD_EOK && ret != KNOTD_EACCES) {
- /*! \todo #1976 Do not reschedule if zone is being discarded. */
if (zd != NULL && !knot_zone_contents(xfr.zone)) {
/* Reschedule request (120 - 240s random delay). */
int tmr_s = AXFR_BOOTSTRAP_RETRY * 2; /* Malus x2 */
diff --git a/src/knot/server/zones.c b/src/knot/server/zones.c
index edec93affd8bc8ba224f5659f73e15388e06d960..8a1896a5b78e823cd2ca9d39550dc93e4c9d9f85 100644
--- a/src/knot/server/zones.c
+++ b/src/knot/server/zones.c
@@ -305,6 +305,12 @@ static int zones_expire_ev(event_t *e)
zonedata_t *zd = (zonedata_t *)zone->data;
rcu_read_lock();
+ /* Check if zone is not discarded. */
+ if (knot_zone_flags(zone) & KNOT_ZONE_DISCARDED) {
+ rcu_read_unlock();
+ return KNOTD_EOK;
+ }
+
/* Do not issue SOA query if transfer is pending. */
int locked = pthread_mutex_trylock(&zd->xfr_in.lock);
if (locked != 0) {
@@ -340,6 +346,8 @@ static int zones_expire_ev(event_t *e)
}
/* Publish expired zone. */
+ /* Need to keep a reference in case zone get's deleted in meantime. */
+ knot_zone_retain(zone);
rcu_read_unlock();
synchronize_rcu();
rcu_read_lock();
@@ -368,6 +376,9 @@ static int zones_expire_ev(event_t *e)
pthread_mutex_unlock(&zd->xfr_in.lock);
rcu_read_unlock();
+ /* Release holding reference. */
+ knot_zone_release(zone);
+
return 0;
}
@@ -386,6 +397,12 @@ static int zones_refresh_ev(event_t *e)
/* Cancel pending timers. */
zonedata_t *zd = (zonedata_t *)knot_zone_data(zone);
+
+ /* Check if zone is not discarded. */
+ if (knot_zone_flags(zone) & KNOT_ZONE_DISCARDED) {
+ rcu_read_unlock();
+ return KNOTD_EOK;
+ }
/* Check for contents. */
if (!knot_zone_contents(zone)) {
@@ -454,7 +471,6 @@ static int zones_refresh_ev(event_t *e)
zd->conf->name);
/* Reschedule as RETRY timer. */
- /*! \todo #1976 Do not reschedule if zone is being discarded. */
uint32_t retry_tmr = zones_jitter(zones_soa_retry(zone));
evsched_schedule(e->parent, e, retry_tmr);
dbg_zones("zones: RETRY of '%s' after %u seconds\n",
@@ -479,7 +495,6 @@ static int zones_refresh_ev(event_t *e)
}
/* Reschedule as RETRY timer. */
- /*! \todo #1976 Do not reschedule if zone is being discarded. */
uint32_t retry_tmr = zones_jitter(zones_soa_retry(zone));
evsched_schedule(e->parent, e, retry_tmr);
dbg_zones("zones: RETRY of '%s' after %u seconds\n",
@@ -610,6 +625,12 @@ static int zones_notify_send(event_t *e)
free(ev);
return KNOTD_EINVAL;
}
+
+ /* Check if zone is not discarded. */
+ if (knot_zone_flags(zone) & KNOT_ZONE_DISCARDED) {
+ rcu_read_unlock(); /* Event will be freed on zonedata_destroy.*/
+ return KNOTD_EOK;
+ }
/* Check for answered/cancelled query. */
zonedata_t *zd = (zonedata_t *)knot_zone_data(zone);
@@ -636,7 +657,6 @@ static int zones_notify_send(event_t *e)
int retry_tmr = ev->timeout * 1000;
/* Reschedule. */
- /*! \todo #1976 Do not reschedule if zone is being discarded. */
evsched_schedule(e->parent, e, retry_tmr);
dbg_notify("notify: Query RETRY after %u secs (zone '%s')\n",
retry_tmr / 1000, zd->conf->name);
diff --git a/src/libknot/zone/zonedb.c b/src/libknot/zone/zonedb.c
index 517a006b4e92611acec99d70c35b6500aaf52ddb..43b4489c2febb268f9d0a0648aa5d844e0e7273d 100644
--- a/src/libknot/zone/zonedb.c
+++ b/src/libknot/zone/zonedb.c
@@ -280,6 +280,7 @@ static void delete_zone_from_db(void *node, void *data)
knot_zone_t *zone = (knot_zone_t *)node;
assert(zone);
synchronize_rcu();
+ knot_zone_set_flag(zone, KNOT_ZONE_DISCARDED, 1);
knot_zone_release(zone);
zone = NULL;
}