Torrent Assert When Using Automatic Piece Size

[cyrillicw]

I try to do the following experiment: create torrents of different size on one machine and download them by several others. If I use constant piece size = 16KB, then everything works fine. But if I use automatic piece size (so some torrents have piece size 16 KB and other have piece size 32 KB) then sometimes I catch the following torrent assert:

TORRENT_ASSERT(!m_picker->has_piece_passed(index));

https://github.com/arvidn/libtorrent/tree/RC_2_0/src#L4275

Here is the stack:

raise 0x00007f87128612ab
libtorrent::assert_fail assert.cpp:386
libtorrent::torrent::piece_passed torrent.cpp:4263
libtorrent::torrent::add_hashes torrent.cpp:6781
libtorrent::bt_peer_connection::on_hashes bt_peer_connection.cpp:1494
libtorrent::bt_peer_connection::dispatch_message bt_peer_connection.cpp:2394
libtorrent::bt_peer_connection::dispatch_message bt_peer_connection.cpp:2339
libtorrent::bt_peer_connection::on_receive_impl bt_peer_connection.cpp:4138
libtorrent::bt_peer_connection::on_receive bt_peer_connection.cpp:3087
libtorrent::peer_connection::on_receive_data peer_connection.cpp:6264
libtorrent::aux::handler<libtorrent::peer_connection, void (libtorrent::peer_connection::*)(boost::system::error_code const&, unsigned long), &libtorrent::peer_connection::on_receive_data, &libtorrent::peer_connection::on_error, &libtorrent::peer_connection::on_exception, libtorrent::aux::handler_storage<320ul, (libtorrent::aux::HandlerName)1>, &libtorrent::peer_connection::m_read_handler_storage>::operator()<boost::system::error_code const&, unsigned long> allocating_handler.hpp:334
std::_Function_handler<void (boost::system::error_code const&, unsigned long), libtorrent::aux::handler<libtorrent::peer_connection, void (libtorrent::peer_connection::*)(boost::system::error_code const&, unsigned long), &libtorrent::peer_connection::on_receive_data, &libtorrent::peer_connection::on_error, &libtorrent::peer_connection::on_exception, libtorrent::aux::handler_storage<320ul, (libtorrent::aux::HandlerName)1>, &libtorrent::peer_connection::m_read_handler_storage> >::_M_invoke(std::_Any_data const&, boost::system::error_code const&, unsigned long&&) std_function.h:300
std::function<void (boost::system::error_code const&, unsigned long)>::operator()(boost::system::error_code const&, unsigned long) const std_function.h:688
std::__invoke_impl<void, std::function<void (boost::system::error_code const&, unsigned long)>&, boost::system::error_code&, unsigned long&>(std::__invoke_other, std::function<void (boost::system::error_code const&, unsigned long)>&, boost::system::error_code&, unsigned long&) invoke.h:60
std::__invoke<std::function<void (boost::system::error_code const&, unsigned long)>&, boost::system::error_code&, unsigned long&>(std::function<void (boost::system::error_code const&, unsigned long)>&, boost::system::error_code&, unsigned long&) invoke.h:95
std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>::__call<void, , 0ul, 1ul>(std::tuple<>&&, std::_Index_tuple<0ul, 1ul>) functional:565
std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>::operator()<>() functional:651
boost::asio::asio_handler_invoke<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >(std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>&, ...) handler_invoke_hook.hpp:69
boost_asio_handler_invoke_helpers::invoke<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>, std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >(std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>&, std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>&) handler_invoke_helpers.hpp:37
boost::asio::system_executor::dispatch<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>, std::allocator<void> >(std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)>&&, std::allocator<void> const&) const system_executor.hpp:39
boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >::operator()() work_dispatcher.hpp:59
boost::asio::asio_handler_invoke<boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> > >(boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >&, ...) handler_invoke_hook.hpp:69
boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >, boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> > >(boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >&, boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >&) handler_invoke_helpers.hpp:37
boost::asio::detail::executor_op<boost::asio::detail::work_dispatcher<std::_Bind_result<void, std::function<void (boost::system::error_code const&, unsigned long)> (boost::system::error_code, unsigned long)> >, std::allocator<void>, boost::asio::detail::scheduler_operation>::do_complete(void*, boost::asio::detail::scheduler_operation*, boost::system::error_code const&, unsigned long) executor_op.hpp:70
boost::asio::detail::scheduler_operation::complete scheduler_operation.hpp:40
boost::asio::detail::scheduler::do_run_one scheduler.ipp:447
boost::asio::detail::scheduler::run scheduler.ipp:200
boost::asio::io_context::run io_context.ipp:63
sirius::drive::DefaultReplicator::start()::{lambda()#2}::operator()() const Replicator.cpp:203
std::__invoke_impl<void, sirius::drive::DefaultReplicator::start()::{lambda()#2}>(std::__invoke_other, sirius::drive::DefaultReplicator::start()::{lambda()#2}&&) invoke.h:60
std::__invoke<sirius::drive::DefaultReplicator::start()::{lambda()#2}>(sirius::drive::DefaultReplicator::start()::{lambda()#2}&&) invoke.h:95
std::thread::_Invoker<std::tuple<sirius::drive::DefaultReplicator::start()::{lambda()#2}> >::_M_invoke<0ul>(std::_Index_tuple<0ul>) thread:244
std::thread::_Invoker<std::tuple<sirius::drive::DefaultReplicator::start()::{lambda()#2}> >::operator()() thread:251
std::thread::_State_impl<std::thread::_Invoker<std::tuple<sirius::drive::DefaultReplicator::start()::{lambda()#2}> > >::_M_run() thread:195
<unknown> 0x00007f871273fde4
start_thread 0x00007f8712855609
clone 0x00007f871257b133

[arvidn]

does this happen consistently with certain torrents you generate?
Is there any chance you could help me reproduce this or have a stress test as part of libtorrent CI?

[cyrillicw]

Will generate a reproducible example in a few days

[cyrillicw]

Here is an example https://github.com/cyrillicw/LibtorrentExample

[cyrillicw]

In this example five downloaders try to download 1GB file from the single uploader and other downloaders. In order to run it you have to bind ip addresses - you can do it with create_ip.sh script

[cyrillicw]

The assert does not arise always but quite often

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.