SIGABRT in ~ProxyClientBase with #29409 and rust client

[ryanofsky]

Originally posted by @TheCharlatan in bitcoin/bitcoin#29409 (comment)

Thanks for the rebase :)

I updated darosior's core_bdk_wallet to use this newest version and I ran into a few crashes again. This is the one I managed to get a reproducible backtrace for:

Crash backtrace + ipc debug logging

2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server post request  #32 {bitcoin-node-165737/b-capnp-loop-166141 (from )}
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server send response #32 Chain.handleNotifications$Results (result = <external capability>)
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server destroy N2mp11ProxyServerIN3ipc5capnp8messages7HandlerEEE
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165873} IPC client destroy N2mp11ProxyClientIN3ipc5capnp8messages18ChainNotificationsEEE
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165873} IPC client first request from current thread, constructing waiter
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165873} IPC client send ChainNotifications.destroy$Params (context = (thread = <external capability>, callbackThread = <external capability>))
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server destroy N2mp11ProxyServerIN3ipc5capnp8messages5ChainEEE
2025-09-29T11:18:20Z [ipc] IPC client method call interrupted by disconnect.
terminate called after throwing an instance of 'ipc::Exception'
  what():  IPC client method call interrupted by disconnect.
[Thread 0x7ffed37fe6c0 (LWP 166141) exited]
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server: socket disconnected.
2025-09-29T11:18:20Z [ipc] {bitcoin-node-165737/b-capnp-loop-165742} IPC server destroy N2mp11ProxyServerIN3ipc5capnp8messages4InitEEE

Thread 45 "b-capnp-loop" received signal SIGABRT, Aborted.
[Switching to Thread 0x7ffed2ffd6c0 (LWP 165873)]
__pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:44
warning: 44	./nptl/pthread_kill.c: No such file or directory
(gdb) bt
#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:44
#1  __pthread_kill_internal (signo=6, threadid=<optimized out>) at ./nptl/pthread_kill.c:78
#2  __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:89
#3  0x00007ffff724527e in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#4  0x00007ffff72288ff in __GI_abort () at ./stdlib/abort.c:79
#5  0x00007ffff76a5ff5 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#6  0x00007ffff76bb0da in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#7  0x00007ffff76a5a55 in std::terminate() () from /lib/x86_64-linux-gnu/libstdc++.so.6
#8  0x000055555563c47f in __clang_call_terminate ()
#9  0x0000555555b39999 in mp::ProxyClientBase<ipc::capnp::messages::ChainNotifications, interfaces::Chain::Notifications>::~ProxyClientBase (this=0x7ffed40cfe60)
    at ./ipc/libmultiprocess/include/mp/proxy-io.h:468
#10 0x0000555555b36e9f in mp::ProxyClient<ipc::capnp::messages::ChainNotifications>::~ProxyClient (this=0x28769)
    at /home/drgrid/bitcoin/build_dev_mode_clang/src/ipc/capnp/chain.capnp.proxy-types.c++:12
#11 0x000055555575637e in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release (this=0x7ffed40049a0)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:346
#12 std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1071
#13 std::__shared_ptr<interfaces::Chain::Notifications, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1524
#14 node::(anonymous namespace)::NotificationsProxy::~NotificationsProxy (this=<optimized out>) at ./node/interfaces.cpp:456
#15 0x0000555555755fbc in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release (this=0x7ffed4000d80)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:346
#16 std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1071
#17 std::__shared_ptr<node::(anonymous namespace)::NotificationsProxy, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1524
#18 std::__shared_ptr<node::(anonymous namespace)::NotificationsProxy, (__gnu_cxx::_Lock_policy)2>::reset (this=0x7ffed4005a50)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1642
#19 node::(anonymous namespace)::NotificationsHandlerImpl::disconnect (this=0x7ffed4005a40) at ./node/interfaces.cpp:496
#20 0x0000555555755e47 in node::(anonymous namespace)::NotificationsHandlerImpl::~NotificationsHandlerImpl (this=0x7ffed4005a40) at ./node/interfaces.cpp:491
#21 node::(anonymous namespace)::NotificationsHandlerImpl::~NotificationsHandlerImpl (this=0x28769) at ./node/interfaces.cpp:491
#22 0x0000555555b49cb7 in std::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release (this=0x7ffed4004d00)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:346
#23 std::__shared_count<(__gnu_cxx::_Lock_policy)2>::~__shared_count (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1071
#24 std::__shared_ptr<interfaces::Handler, (__gnu_cxx::_Lock_policy)2>::~__shared_ptr (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1524
#25 std::__shared_ptr<interfaces::Handler, (__gnu_cxx::_Lock_policy)2>::reset (this=0x7fffe801c3e0)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/shared_ptr_base.h:1642
#26 mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}::operator()() (this=0x7fffe801c3e0)
    at ./ipc/libmultiprocess/include/mp/proxy-io.h:514
#27 std::__invoke_impl<void, mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}&>(std::__invoke_other, mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}&) (__f=...) at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/invoke.h:61
#28 std::__invoke_r<void, mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}&>(mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}&) (__fn=...) at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/invoke.h:111
#29 std::_Function_handler<void (), mp::ProxyServerBase<ipc::capnp::messages::Handler, interfaces::Handler>::~ProxyServerBase()::{lambda()#1}>::_M_invoke(std::_Any_data const&) (
    __functor=...) at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/std_function.h:290
#30 0x0000555555f41979 in std::function<void ()>::operator()() const (this=0x7ffed2ffca70) at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/std_function.h:591
#31 mp::Unlock<mp::Lock, std::function<void ()> const&>(mp::Lock&, std::function<void ()> const&) (lock=..., callback=...) at ./ipc/libmultiprocess/include/mp/util.h:209
#32 0x0000555555f3f56f in mp::EventLoop::startAsyncThread()::$_0::operator()() const (this=<optimized out>) at ./ipc/libmultiprocess/src/mp/proxy.cpp:298
#33 std::__invoke_impl<void, mp::EventLoop::startAsyncThread()::$_0>(std::__invoke_other, mp::EventLoop::startAsyncThread()::$_0&&) (__f=...)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/invoke.h:61
#34 std::__invoke<mp::EventLoop::startAsyncThread()::$_0>(mp::EventLoop::startAsyncThread()::$_0&&) (__fn=...)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/invoke.h:96
#35 std::thread::_Invoker<std::tuple<mp::EventLoop::startAsyncThread()::$_0> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/std_thread.h:292
#36 std::thread::_Invoker<std::tuple<mp::EventLoop::startAsyncThread()::$_0> >::operator()() (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/std_thread.h:299
#37 std::thread::_State_impl<std::thread::_Invoker<std::tuple<mp::EventLoop::startAsyncThread()::$_0> > >::_M_run() (this=<optimized out>)
    at /usr/bin/../lib/gcc/x86_64-linux-gnu/13/../../../../include/c++/13/bits/std_thread.h:244
#38 0x00007ffff76ecdb4 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#39 0x00007ffff729caa4 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:447
#40 0x00007ffff7329c6c in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

[ryanofsky]

Seems that an exception is being thrown from the ~ProxyServerBase() destructor, causing std::terminate to be called. I'll need to look into stack trace more to try to figure out the how this is happening. Hopefully it should not be too hard to write a unit test to reproduce it.