TSAN error in xfrin.c

Job #1632017 failed for a0075ea9:

Pre netmgr xfrin was task constrained, this is no longer true.

WARNING: ThreadSanitizer: data race 
  Read of size 8 at 0x000000000001 by thread T1:
    #0 xfrin_fail lib/dns/xfrin.c:808
    #1 xfrin_recv_done lib/dns/xfrin.c:1485
    #2 isc__nm_async_readcb netmgr/netmgr.c:2411
    #3 process_netievent netmgr/netmgr.c:743
    #4 process_queue netmgr/netmgr.c:766
    #5 process_normal_queue netmgr/netmgr.c:652
    #6 process_queues netmgr/netmgr.c:660
    #7 async_cb netmgr/netmgr.c:618
    #8 <null> <null>
    #9 isc__trampoline_run lib/isc/trampoline.c:184
    #10 <null> <null>

  Previous write of size 8 at 0x000000000001 by thread T2:
    #0 xfrin_fail lib/dns/xfrin.c:810
    #1 dns_xfrin_shutdown lib/dns/xfrin.c:725
    #2 zone_shutdown lib/dns/zone.c:14648
    #3 dispatch lib/isc/task.c:1153
    #4 run lib/isc/task.c:1345
    #5 isc__trampoline_run lib/isc/trampoline.c:184
    #6 <null> <null>

  Location is heap block of size 1352 at 0x000000000015 allocated by thread T3:
    #0 malloc <null>
    #1 default_memalloc lib/isc/mem.c:411
    #2 mem_get lib/isc/mem.c:343
    #3 mem_allocateunlocked lib/isc/mem.c:918
    #4 isc__mem_allocate lib/isc/mem.c:935
    #5 isc__mem_get lib/isc/mem.c:740
    #6 xfrin_create lib/dns/xfrin.c:825
    #7 dns_xfrin_create lib/dns/xfrin.c:679
    #8 got_transfer_quota lib/dns/zone.c:17798
    #9 dispatch lib/isc/task.c:1153
    #10 run lib/isc/task.c:1345
    #11 isc__trampoline_run lib/isc/trampoline.c:184
    #12 <null> <null>

  Thread T1 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create pthreads/thread.c:79
    #2 isc_nm_start netmgr/netmgr.c:293
    #3 create_managers bin/named/main.c:954
    #4 setup bin/named/main.c:1268
    #5 main bin/named/main.c:1559

  Thread T2 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create pthreads/thread.c:79
    #2 isc_taskmgr_create lib/isc/task.c:1435
    #3 create_managers bin/named/main.c:960
    #4 setup bin/named/main.c:1268
    #5 main bin/named/main.c:1559

  Thread T3 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create pthreads/thread.c:79
    #2 isc_taskmgr_create lib/isc/task.c:1435
    #3 create_managers bin/named/main.c:960
    #4 setup bin/named/main.c:1268
    #5 main bin/named/main.c:1559

SUMMARY: ThreadSanitizer: data race lib/dns/xfrin.c:808 in xfrin_fail

also

WARNING: ThreadSanitizer: data race 
  Write of size 1 at 0x000000000001 by thread T1:
    #0 xfrin_fail lib/dns/xfrin.c:812
    #1 dns_xfrin_shutdown lib/dns/xfrin.c:725
    #2 zone_shutdown lib/dns/zone.c:14648
    #3 dispatch lib/isc/task.c:1153
    #4 run lib/isc/task.c:1345
    #5 isc__trampoline_run lib/isc/trampoline.c:184
    #6 <null> <null>

  Previous read of size 1 at 0x000000000001 by thread T2:
    #0 xfrin_recv_done lib/dns/xfrin.c:1215
    #1 isc__nm_async_readcb netmgr/netmgr.c:2411
    #2 process_netievent netmgr/netmgr.c:743
    #3 process_queue netmgr/netmgr.c:766
    #4 process_normal_queue netmgr/netmgr.c:652
    #5 process_queues netmgr/netmgr.c:660
    #6 async_cb netmgr/netmgr.c:618
    #7 <null> <null>
    #8 isc__trampoline_run lib/isc/trampoline.c:184
    #9 <null> <null>

  Thread T1 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create pthreads/thread.c:79
    #2 isc_taskmgr_create lib/isc/task.c:1435
    #3 create_managers bin/named/main.c:960
    #4 setup bin/named/main.c:1268
    #5 main bin/named/main.c:1559

  Thread T2 (running) created by main thread at:
    #0 pthread_create <null>
    #1 isc_thread_create pthreads/thread.c:79
    #2 isc_nm_start netmgr/netmgr.c:293
    #3 create_managers bin/named/main.c:954
    #4 setup bin/named/main.c:1268
    #5 main bin/named/main.c:1559

SUMMARY: ThreadSanitizer: data race lib/dns/xfrin.c:812 in xfrin_fail