diff --git a/src/knot/server/notify.c b/src/knot/server/notify.c
index 78b5480f3cfb202e38dfd413bbe6f6cbcff2705c..d0292e8ff847c822a01bcf4d494b1b7e770871b9 100644
--- a/src/knot/server/notify.c
+++ b/src/knot/server/notify.c
@@ -270,10 +270,12 @@ int notify_process_request(knot_nameserver_t *ns,
}
// find the zone
+ rcu_read_lock();
const knot_dname_t *qname = knot_packet_qname(notify);
const knot_zone_t *z = knot_zonedb_find_zone_for_name(
ns->zone_db, qname);
if (z == NULL) {
+ rcu_read_unlock();
dbg_notify("notify: failed to find zone by name\n");
knot_ns_error_response_from_query(ns, notify,
KNOT_RCODE_FORMERR, buffer,
@@ -282,7 +284,7 @@ int notify_process_request(knot_nameserver_t *ns,
}
notify_check_and_schedule(ns, z, from);
-
+ rcu_read_unlock();
return KNOTD_EOK;
}
@@ -302,13 +304,16 @@ int notify_process_response(knot_nameserver_t *nameserver,
*size = 0;
/* Find matching zone. */
+ rcu_read_lock();
const knot_dname_t *zone_name = knot_packet_qname(notify);
knot_zone_t *zone = knot_zonedb_find_zone(nameserver->zone_db,
zone_name);
if (!zone) {
+ rcu_read_unlock();
return KNOTD_ENOENT;
}
if (!knot_zone_data(zone)) {
+ rcu_read_unlock();
return KNOTD_ENOENT;
}
@@ -326,6 +331,7 @@ int notify_process_response(knot_nameserver_t *nameserver,
/* Found waiting NOTIFY query? */
if (!match) {
+ rcu_read_unlock();
pthread_mutex_unlock(&zd->lock);
return KNOTD_ERROR;
}
@@ -335,6 +341,8 @@ int notify_process_response(knot_nameserver_t *nameserver,
/* Zone was removed/reloaded. */
pthread_mutex_unlock(&zd->lock);
+
+ rcu_read_unlock();
return KNOTD_EOK;
}
diff --git a/src/knot/server/xfr-handler.c b/src/knot/server/xfr-handler.c
index eb11c89c2037c7543add5329bbf04244c029d37d..f52ea779ef967f45ff99a37d4330cd7e14f74809 100644
--- a/src/knot/server/xfr-handler.c
+++ b/src/knot/server/xfr-handler.c
@@ -93,6 +93,9 @@ static void xfr_free_task(knot_ns_xfr_t *task)
}
}
+ /* No further access to zone. */
+ knot_zone_release(task->zone);
+
/* Deinitialize */
xfr_request_deinit(task);
if (!task->session_closed) {
@@ -1289,6 +1292,7 @@ int xfr_answer(knot_nameserver_t *ns, knot_ns_xfr_t *xfr)
return KNOTD_EINVAL;
}
+ rcu_read_lock();
int ret = knot_ns_init_xfr(ns, xfr);
int xfr_failed = (ret != KNOT_EOK);
@@ -1372,6 +1376,7 @@ int xfr_answer(knot_nameserver_t *ns, knot_ns_xfr_t *xfr)
free(xfr->tsig_data);
xfr->tsig_data = NULL;
xfr_request_deinit(xfr);
+ rcu_read_unlock();
/* Cleanup. */
free(xfr->digest);
@@ -1423,6 +1428,7 @@ 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 */
@@ -1439,6 +1445,7 @@ static int xfr_process_request(xfrworker_t *w, uint8_t *buf, size_t buflen)
log_server_error("%s %s\n",
xfr.msgpref, knotd_strerror(ret));
}
+ knot_zone_release(xfr.zone); /* No further access to zone. */
}
break;
@@ -1447,14 +1454,14 @@ static int xfr_process_request(xfrworker_t *w, uint8_t *buf, size_t buflen)
/* Register task. */
task = xfr_register_task(w, &xfr);
if (!task) {
+ knot_zone_release(xfr.zone); /* No further access to zone. */
ret = KNOTD_ENOMEM;
- break;
+ } else {
+ /* Add timeout. */
+ fdset_set_watchdog(w->fdset, task->session, XFR_QUERY_WD);
+ log_server_info("%s Query issued.\n", xfr.msgpref);
+ ret = KNOTD_EOK;
}
-
- /* Add timeout. */
- fdset_set_watchdog(w->fdset, task->session, XFR_QUERY_WD);
- log_server_info("%s Query issued.\n", xfr.msgpref);
- ret = KNOTD_EOK;
break;
default:
log_server_error("Unknown XFR request type (%d).\n", xfr.type);
diff --git a/src/knot/server/zones.c b/src/knot/server/zones.c
index 65ad797c47e866b2653de4ec99192f56b70a80a0..edec93affd8bc8ba224f5659f73e15388e06d960 100644
--- a/src/knot/server/zones.c
+++ b/src/knot/server/zones.c
@@ -377,8 +377,10 @@ static int zones_expire_ev(event_t *e)
static int zones_refresh_ev(event_t *e)
{
dbg_zones("zones: REFRESH or RETRY timer event\n");
+ rcu_read_lock();
knot_zone_t *zone = (knot_zone_t *)e->data;
if (zone == NULL || zone->data == NULL) {
+ rcu_read_unlock();
return KNOTD_EINVAL;
}
@@ -386,7 +388,6 @@ static int zones_refresh_ev(event_t *e)
zonedata_t *zd = (zonedata_t *)knot_zone_data(zone);
/* Check for contents. */
- rcu_read_lock();
if (!knot_zone_contents(zone)) {
/* Bootstrap from XFR master. */
@@ -429,13 +430,20 @@ static int zones_refresh_ev(event_t *e)
++zd->xfr_in.scheduled;
pthread_mutex_unlock(&zd->xfr_in.lock);
+ /* Retain pointer to zone for processing. */
+ knot_zone_retain(xfr_req.zone);
+
/* Unlock zone contents. */
rcu_read_unlock();
/* Mark as finished to prevent stalling. */
evsched_event_finished(e->parent);
+ int ret = xfr_request(zd->server->xfr_h, &xfr_req);
+ if (ret != KNOTD_EOK) {
+ knot_zone_release(xfr_req.zone); /* Discard */
+ }
+ return ret;
- return xfr_request(zd->server->xfr_h, &xfr_req);
}
/* Do not issue SOA query if transfer is pending. */
@@ -446,6 +454,7 @@ 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",
@@ -470,6 +479,7 @@ 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",
@@ -558,10 +568,14 @@ static int zones_refresh_ev(event_t *e)
memcpy(&req.saddr, &zd->xfr_in.via, sizeof(sockaddr_t));
sockaddr_update(&req.addr);
sockaddr_update(&req.saddr);
+
+ /* Retain pointer to zone and issue. */
+ knot_zone_retain(req.zone);
if (ret == KNOTD_EOK) {
ret = xfr_request(zd->server->xfr_h, &req);
}
if (ret != KNOTD_EOK) {
+ knot_zone_release(req.zone); /* Discard */
log_server_warning("Failed to issue SOA query for zone '%s' (%s).\n",
zd->conf->name, errstr);
}
@@ -580,22 +594,23 @@ static int zones_refresh_ev(event_t *e)
static int zones_notify_send(event_t *e)
{
dbg_notify("notify: NOTIFY timer event\n");
-
+ rcu_read_lock();
notify_ev_t *ev = (notify_ev_t *)e->data;
if (ev == NULL) {
+ rcu_read_unlock();
log_zone_error("NOTIFY invalid event received\n");
return KNOTD_EINVAL;
}
+
knot_zone_t *zone = ev->zone;
if (zone == NULL || zone->data == NULL) {
+ rcu_read_unlock();
log_zone_error("NOTIFY invalid event data received\n");
evsched_event_free(e->parent, e);
free(ev);
return KNOTD_EINVAL;
}
- rcu_read_lock();
-
/* Check for answered/cancelled query. */
zonedata_t *zd = (zonedata_t *)knot_zone_data(zone);
knot_zone_contents_t *contents = knot_zone_get_contents(zone);
@@ -621,6 +636,7 @@ 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);
@@ -675,7 +691,13 @@ static int zones_notify_send(event_t *e)
req.zone = zone;
memcpy(&req.addr, &ev->addr, sizeof(sockaddr_t));
memcpy(&req.saddr, &ev->saddr, sizeof(sockaddr_t));
- xfr_request(zd->server->xfr_h, &req);
+
+ /* Retain pointer to zone and issue request. */
+ knot_zone_retain(req.zone);
+ ret = xfr_request(zd->server->xfr_h, &req);
+ if (ret != KNOTD_EOK) {
+ knot_zone_release(req.zone); /* Discard */
+ }
}
free(qbuf);
@@ -2440,6 +2462,7 @@ int zones_process_response(knot_nameserver_t *nameserver,
}
/* Find matching zone and ID. */
+ rcu_read_lock();
const knot_dname_t *zone_name = knot_packet_qname(packet);
/*! \todo Change the access to the zone db. */
knot_zone_t *zone = knot_zonedb_find_zone(
@@ -2447,7 +2470,6 @@ int zones_process_response(knot_nameserver_t *nameserver,
zone_name);
/* Get zone contents. */
- rcu_read_lock();
const knot_zone_contents_t *contents =
knot_zone_contents(zone);
@@ -2526,9 +2548,13 @@ int zones_process_response(knot_nameserver_t *nameserver,
/* Unlock zone contents. */
rcu_read_unlock();
- /* Enqueue XFR request. */
- return xfr_request(((server_t *)knot_ns_get_data(
- nameserver))->xfr_h, &xfr_req);
+ /* Retain pointer to zone for processing. */
+ knot_zone_retain(xfr_req.zone);
+ ret = xfr_request(((server_t *)knot_ns_get_data(
+ nameserver))->xfr_h, &xfr_req);
+ if (ret != KNOTD_EOK) {
+ knot_zone_release(xfr_req.zone); /* Discard */
+ }
}
return KNOTD_EOK;
diff --git a/src/libknot/nameserver/name-server.c b/src/libknot/nameserver/name-server.c
index d214763739194f29608db519c4a27ae07138df35..134fa8a6596138982d94f15976a77bc587eda3af 100644
--- a/src/libknot/nameserver/name-server.c
+++ b/src/libknot/nameserver/name-server.c
@@ -3936,9 +3936,9 @@ int knot_ns_switch_zone(knot_nameserver_t *nameserver,
return KNOT_ENOZONE;
}
- // find the zone in the zone db
- knot_zone_t *z = knot_zonedb_find_zone(nameserver->zone_db,
- knot_node_owner(knot_zone_contents_apex(zone)));
+ /* Zone must not be looked-up from server, as it may be a different zone if
+ * a reload occurs when transfer is pending. */
+ knot_zone_t *z = xfr->zone;
if (z == NULL) {
char *name = knot_dname_to_str(knot_node_owner(
knot_zone_contents_apex(zone)));
@@ -3957,6 +3957,8 @@ dbg_ns_exec_verb(
dbg_ns_verb("Zone db contents: (zone count: %zu)\n",
nameserver->zone_db->zone_count);
+ /* Warning: may not show updated zone if updated zone that is already
+ * discarded from zone db (reload with pending transfer). */
const knot_zone_t **zones = knot_zonedb_zones(nameserver->zone_db);
for (int i = 0; i < knot_zonedb_zone_count
(nameserver->zone_db); i++) {