[DISPATCH-2123] qd_entity_refresh_allocator race in alloc_pool.c

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.16.0
• Fix Version/s: 1.20.0
• Component/s: Router Node
• Labels: race-condition tsan
• Assignee: Ken Giusti
• Reporter: Ken Giusti
• Created: 17/May/21 20:42
• Updated: 15/Mar/22 21:54

Description

qd_entity_refresh_allocator walks all the descriptors reading their contents.  This can happen while the descriptors are being written to during normal pool operations.

 

Example:

 

5: WARNING: ThreadSanitizer: data race (pid=566878)
65: Read of size 8 at 0x7b0c00000d10 by main thread (mutexes: write M13, write M286, write M9):
65: #0 qd_entity_refresh_allocator /home/kgiusti/work/dispatch/qpid-dispatch/src/alloc_pool.c:700 (libqpid-dispatch.so+0x6cdec)
65: #1 ffi_call_unix64 <null> (libffi.so.6+0x6aef)
65: #2 qdr_forward_on_message /home/kgiusti/work/dispatch/qpid-dispatch/src/router_core/forwarder.c:336 (libqpid-dispatch.so+0xe4ff5)
65: #3 qdr_general_handler /home/kgiusti/work/dispatch/qpid-dispatch/src/router_core/router_core.c:929 (libqpid-dispatch.so+0xf83f6)
65: #4 qd_timer_visit /home/kgiusti/work/dispatch/qpid-dispatch/src/timer.c:317 (libqpid-dispatch.so+0x135b52)
65: #5 handle /home/kgiusti/work/dispatch/qpid-dispatch/src/server.c:1006 (libqpid-dispatch.so+0x12fc8d)
65: #6 thread_run /home/kgiusti/work/dispatch/qpid-dispatch/src/server.c:1121 (libqpid-dispatch.so+0x13063a)
65: #7 qd_server_run /home/kgiusti/work/dispatch/qpid-dispatch/src/server.c:1501 (libqpid-dispatch.so+0x1328de)
65: #8 main_process /home/kgiusti/work/dispatch/qpid-dispatch/router/src/main.c:115 (qdrouterd+0x40271a)
65: #9 main /home/kgiusti/work/dispatch/qpid-dispatch/router/src/main.c:369 (qdrouterd+0x403557)
65:
65: Previous write of size 8 at 0x7b0c00000d10 by thread T1 (mutexes: write M305):
65: #0 qd_dealloc /home/kgiusti/work/dispatch/qpid-dispatch/src/alloc_pool.c:494 (libqpid-dispatch.so+0x6bacd)
65: #1 free_qdr_action_t /home/kgiusti/work/dispatch/qpid-dispatch/src/router_core/router_core_thread.c:33 (libqpid-dispatch.so+0xf9a35)
65: #2 router_core_thread /home/kgiusti/work/dispatch/qpid-dispatch/src/router_core/router_core_thread.c:240 (libqpid-dispatch.so+0xfb2ba)
65: #3 _thread_init /home/kgiusti/work/dispatch/qpid-dispatch/src/posix/threading.c:172 (libqpid-dispatch.so+0xad37a)
65: #4 <null> <null> (libtsan.so.0+0x2d33f)