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Address lock-order-inversion

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Obtain references to view->redirect and view->managed_keys then
release view->lock so dns_zone_setviewcommit and dns_zone_setviewrevert
can obtain the view->lock while holding zone->lock.

WARNING: ThreadSanitizer: lock-order-inversion (potential deadlock) (pid=9132)
  Cycle in lock order graph: M987831431424375936 (0x000000000000) => M1012319771577875480 (0x000000000000) => M987831431424375936

  Mutex M1012319771577875480 acquired here while holding mutex M987831431424375936 in thread T2:
    #0 pthread_mutex_lock <null> (named+0x4642a6)
    #1 dns_zone_setviewcommit /builds/isc-projects/bind9/lib/dns/zone.c:1571:2 (libdns.so.1110+0x1d74eb)
    #2 dns_view_setviewcommit /builds/isc-projects/bind9/lib/dns/view.c:2388:3 (libdns.so.1110+0x1cfe29)
    #3 load_configuration /builds/isc-projects/bind9/bin/named/./server.c:8188:3 (named+0x51eadd)
    #4 loadconfig /builds/isc-projects/bind9/bin/named/./server.c:9438:11 (named+0x510c66)
    #5 ns_server_reconfigcommand /builds/isc-projects/bind9/bin/named/./server.c:9773:2 (named+0x510b41)
    #6 ns_control_docommand /builds/isc-projects/bind9/bin/named/control.c:243:12 (named+0x4e451a)
    #7 control_recvmessage /builds/isc-projects/bind9/bin/named/controlconf.c:465:13 (named+0x4e9056)
    #8 dispatch /builds/isc-projects/bind9/lib/isc/task.c:1157:7 (libisc.so.1107+0x507d5)
    #9 run /builds/isc-projects/bind9/lib/isc/task.c:1331:2 (libisc.so.1107+0x4d729)

  Mutex M987831431424375936 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null> (named+0x4642a6)
    #1 dns_view_setviewcommit /builds/isc-projects/bind9/lib/dns/view.c:2382:2 (libdns.so.1110+0x1cfde7)
    #2 load_configuration /builds/isc-projects/bind9/bin/named/./server.c:8188:3 (named+0x51eadd)
    #3 loadconfig /builds/isc-projects/bind9/bin/named/./server.c:9438:11 (named+0x510c66)
    #4 ns_server_reconfigcommand /builds/isc-projects/bind9/bin/named/./server.c:9773:2 (named+0x510b41)
    #5 ns_control_docommand /builds/isc-projects/bind9/bin/named/control.c:243:12 (named+0x4e451a)
    #6 control_recvmessage /builds/isc-projects/bind9/bin/named/controlconf.c:465:13 (named+0x4e9056)
    #7 dispatch /builds/isc-projects/bind9/lib/isc/task.c:1157:7 (libisc.so.1107+0x507d5)
    #8 run /builds/isc-projects/bind9/lib/isc/task.c:1331:2 (libisc.so.1107+0x4d729)

  Mutex M987831431424375936 acquired here while holding mutex M1012319771577875480 in thread T7:
    #0 pthread_mutex_lock <null> (named+0x4642a6)
    #1 dns_view_findzonecut2 /builds/isc-projects/bind9/lib/dns/view.c:1300:2 (libdns.so.1110+0x1cc93a)
    #2 dns_view_findzonecut /builds/isc-projects/bind9/lib/dns/view.c:1261:9 (libdns.so.1110+0x1cc864)
    #3 fctx_create /builds/isc-projects/bind9/lib/dns/resolver.c:4459:13 (libdns.so.1110+0x1779d3)
    #4 dns_resolver_createfetch3 /builds/isc-projects/bind9/lib/dns/resolver.c:9628:12 (libdns.so.1110+0x176cb6)
    #5 dns_resolver_createfetch /builds/isc-projects/bind9/lib/dns/resolver.c:9504:10 (libdns.so.1110+0x174e17)
    #6 zone_refreshkeys /builds/isc-projects/bind9/lib/dns/zone.c:10061:12 (libdns.so.1110+0x2055a5)
    #7 zone_maintenance /builds/isc-projects/bind9/lib/dns/zone.c:10274:5 (libdns.so.1110+0x203a78)
    #8 zone_timer /builds/isc-projects/bind9/lib/dns/zone.c:13106:2 (libdns.so.1110+0x1e815a)
    #9 dispatch /builds/isc-projects/bind9/lib/isc/task.c:1157:7 (libisc.so.1107+0x507d5)
    #10 run /builds/isc-projects/bind9/lib/isc/task.c:1331:2 (libisc.so.1107+0x4d729)

  Mutex M1012319771577875480 previously acquired by the same thread here:
    #0 pthread_mutex_lock <null> (named+0x4642a6)
    #1 zone_refreshkeys /builds/isc-projects/bind9/lib/dns/zone.c:9951:2 (libdns.so.1110+0x204dc3)
    #2 zone_maintenance /builds/isc-projects/bind9/lib/dns/zone.c:10274:5 (libdns.so.1110+0x203a78)
    #3 zone_timer /builds/isc-projects/bind9/lib/dns/zone.c:13106:2 (libdns.so.1110+0x1e815a)
    #4 dispatch /builds/isc-projects/bind9/lib/isc/task.c:1157:7 (libisc.so.1107+0x507d5)
    #5 run /builds/isc-projects/bind9/lib/isc/task.c:1331:2 (libisc.so.1107+0x4d729)

  Thread T2 'isc-worker0001' (tid=9163, running) created by main thread at:
    #0 pthread_create <null> (named+0x446edb)
    #1 isc_thread_create /builds/isc-projects/bind9/lib/isc/pthreads/thread.c:60:8 (libisc.so.1107+0x726d8)
    #2 isc__taskmgr_create /builds/isc-projects/bind9/lib/isc/task.c:1468:7 (libisc.so.1107+0x4d635)
    #3 isc_taskmgr_create /builds/isc-projects/bind9/lib/isc/task.c:2109:11 (libisc.so.1107+0x4f587)
    #4 create_managers /builds/isc-projects/bind9/bin/named/./main.c:886:11 (named+0x4f1a97)
    #5 setup /builds/isc-projects/bind9/bin/named/./main.c:1305:11 (named+0x4f05ee)
    #6 main /builds/isc-projects/bind9/bin/named/./main.c:1556:2 (named+0x4ef12d)

  Thread T7 'isc-worker0006' (tid=9168, running) created by main thread at:
    #0 pthread_create <null> (named+0x446edb)
    #1 isc_thread_create /builds/isc-projects/bind9/lib/isc/pthreads/thread.c:60:8 (libisc.so.1107+0x726d8)
    #2 isc__taskmgr_create /builds/isc-projects/bind9/lib/isc/task.c:1468:7 (libisc.so.1107+0x4d635)
    #3 isc_taskmgr_create /builds/isc-projects/bind9/lib/isc/task.c:2109:11 (libisc.so.1107+0x4f587)
    #4 create_managers /builds/isc-projects/bind9/bin/named/./main.c:886:11 (named+0x4f1a97)
    #5 setup /builds/isc-projects/bind9/bin/named/./main.c:1305:11 (named+0x4f05ee)
    #6 main /builds/isc-projects/bind9/bin/named/./main.c:1556:2 (named+0x4ef12d)

SUMMARY: ThreadSanitizer: lock-order-inversion (potential deadlock) (/builds/isc-projects/bind9/bin/named/.libs/named+0x4642a6) in pthread_mutex_lock
This commit is contained in:
Mark Andrews
2020-08-24 11:44:09 +10:00
parent 552e0b852e
commit cdcfde9e65
1 changed files with 24 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
lib/dns/view.c
View File

@@ -2457,25 +2457,37 @@ cleanup:
void
dns_view_setviewcommit(dns_view_t *view) {
dns_zone_t *redirect = NULL, *managed_keys = NULL;
REQUIRE(DNS_VIEW_VALID(view));
LOCK(&view->lock);
if (view->redirect != NULL) {
dns_zone_setviewcommit(view->redirect);
dns_zone_attach(view->redirect, &redirect);
}
if (view->managed_keys != NULL) {
dns_zone_setviewcommit(view->managed_keys);
dns_zone_attach(view->managed_keys, &managed_keys);
}
if (view->zonetable != NULL) {
dns_zt_setviewcommit(view->zonetable);
}
UNLOCK(&view->lock);
if (redirect != NULL) {
dns_zone_setviewcommit(redirect);
dns_zone_detach(&redirect);
}
if (managed_keys != NULL) {
dns_zone_setviewcommit(managed_keys);
dns_zone_detach(&managed_keys);
}
}
void
dns_view_setviewrevert(dns_view_t *view) {
dns_zone_t *redirect = NULL, *managed_keys = NULL;
dns_zt_t *zonetable;
REQUIRE(DNS_VIEW_VALID(view));
@@ -2486,14 +2498,22 @@ dns_view_setviewrevert(dns_view_t *view) {
*/
LOCK(&view->lock);
if (view->redirect != NULL) {
dns_zone_setviewrevert(view->redirect);
dns_zone_attach(view->redirect, &redirect);
}
if (view->managed_keys != NULL) {
dns_zone_setviewrevert(view->managed_keys);
dns_zone_attach(view->managed_keys, &managed_keys);
}
zonetable = view->zonetable;
UNLOCK(&view->lock);
if (redirect != NULL) {
dns_zone_setviewrevert(redirect);
dns_zone_detach(&redirect);
}
if (managed_keys != NULL) {
dns_zone_setviewrevert(managed_keys);
dns_zone_detach(&managed_keys);
}
if (zonetable != NULL) {
dns_zt_setviewrevert(zonetable);
}