mongo-ruby-driver causes the segfault at program's exit
mongo-ruby-driver 2.11.0 has caused the segfault at program's exit when connecting a certain MongoDB cluster.
I also reported this issue to mongo-ruby-driver.
This is the reproduction example. Please check it out.
You can see full result by using the above example, and also debug it by GDB.
Fetching gem metadata from https://rubygems.org/........ Resolving dependencies... Fetching bson 4.11.1 Installing bson 4.11.1 with native extensions Using bundler 1.17.2 Fetching mongo 2.11.0 Installing mongo 2.11.0 D, [2020-11-27T00:20:31.035863 #11] DEBUG -- : MONGODB | EVENT: #<TopologyOpening topology=Unknown> ... (snip) D, [2020-11-27T00:20:31.145112 #11] DEBUG -- : MONGODB |  mongodb-sharded.cluster.local:27017 | admin.endSessions | SUCCEEDED | 0.000s [BUG] Segmentation fault at 0x0000000000000050 ruby 2.6.6p146 (2020-03-31 revision 67876) [x86_64-linux] -- Control frame information ----------------------------------------------- c:0001 p:---- s:0003 e:000002 (none) [FINISH] -- Machine register context ------------------------------------------------ RIP: 0x00007f52358f4078 RBP: 0x00007f5230b4fdd0 RSP: 0x00007f5230b4fc90 RAX: 0x0000000000000000 RBX: 0x0000563b4b746370 RCX: 0x0000563b44ad4158 RDX: 0x0000563b44ad4570 RDI: 0x0000563b4b8bd318 RSI: 0x0000563b44ad4020 R8: 0x0000000000000011 R9: 0x0000000000000000 R10: 0x0000563b4a8dc050 R11: 0x0000000000000003 R12: 0x0000000000000009 R13: 0x0000563b44b7f630 R14: 0x0000563b46ce6ac0 R15: 0x0000563b498440d8 EFL: 0x0000000000010297 -- C level backtrace information ------------------------------------------- corrupted double-linked list Aborted
- https://bugs.ruby-lang.org/issues/16288 may be a similar issue.
- This commit has caused the segfault.
- It does not happen if this line is commented out.
- Ruby 2.6.6p146 (2020-03-31 revision 67876) [x86_64-linux]
- Ruby 2.7.2p137 (2020-10-01 revision 5445e04352) [x86_64-linux]
Updated by mame (Yusuke Endoh) about 2 months ago
Thank you for the report. I can reproduce and investigated the issue.
I think this is the known (but unfixed) issue #16288. When Ruby process ends, it terminates all threads, run all finalizers, and then destruct everything. However, Mongo gem attempts to create a new thread in a finalizer. In fact, I've observed
native_thread_create is called after
rb_thread_terminate_all returned, and seen the following backtrace by
rb_backtrace() with gdb.
from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/cluster.rb:422:in `block in finalize' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/session/session_pool.rb:118:in `end_sessions' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/op_msg_or_command.rb:27:in `execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:38:in `execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:26:in `do_execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/response_handling.rb:73:in `unpin_maybe' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:27:in `block in do_execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/response_handling.rb:43:in `add_error_labels' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:28:in `block (2 levels) in do_execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/response_handling.rb:87:in `add_server_diagnostics' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:29:in `block (3 levels) in do_execute' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:50:in `get_result' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/operation/shared/executable.rb:55:in `dispatch_message' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server.rb:410:in `with_connection' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server/connection_pool.rb:556:in `with_connection' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server/connection_pool.rb:357:in `check_out' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server/connection_pool.rb:731:in `connect_connection' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server/connection.rb:171:in `connect!' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/server/connection.rb:184:in `do_connect' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address.rb:162:in `socket' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address.rb:202:in `create_resolver' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address.rb:202:in `each' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address.rb:205:in `block in create_resolver' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address/ipv4.rb:93:in `socket' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/address/ipv4.rb:93:in `new' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/socket/tcp.rb:67:in `initialize' from /usr/local/bundle/gems/mongo-2.11.0/lib/mongo/socket/tcp.rb:41:in `connect!' from /usr/local/lib/ruby/2.6.0/timeout.rb:103:in `timeout' from /usr/local/lib/ruby/2.6.0/timeout.rb:83:in `block in timeout' from /usr/local/lib/ruby/2.6.0/timeout.rb:83:in `start'