Msgid with string type can crash any rpclib server (even with exceptions suppressed)

[l0ud]

If client is sending msgid as String instead of integer server will crash with clmdep_msgpack::v1::type_error exception.

Exception is happening inside msg.convert(the_call); in dispatcher.cc

I found that error is triggered when using the following PHP library:
https://github.com/funeralzone/MsgPackPhp
which apparently has a bug and is sending "0" (string) as msgid (instead of numeric 0)

call stack

2   abort                                                                                                                                                       0x7fcec4c2d862 
3   __gnu_cxx::__verbose_terminate_handler                                                                                                 vterminate.cc    95  0x7fcec4fec802 
4   __cxxabiv1::__terminate                                                                                                                eh_terminate.cc  48  0x7fcec4ff8c8a 
5   std::terminate                                                                                                                         eh_terminate.cc  58  0x7fcec4ff8cf7 
6   __cxxabiv1::__cxa_throw                                                                                                                eh_throw.cc      95  0x7fcec4ff8f8e 
7   clmdep_msgpack::v1::type::detail::convert_integer_sign<unsigned int, false>::convert                                                   int.hpp          51  0x55f9eef800b9 
8   clmdep_msgpack::v1::type::detail::convert_integer<unsigned int>                                                                        int.hpp          63  0x55f9eef7e94f 
9   clmdep_msgpack::v1::adaptor::convert<unsigned int, void>::operator()                                                                   int.hpp          150 0x55f9eef7d6ca 
10  clmdep_msgpack::v1::operator>><unsigned int>                                                                                           adaptor_base.hpp 58  0x55f9eef88497 
11  clmdep_msgpack::v1::object::convert<unsigned int>                                                                                      object.hpp       549 0x55f9eef88125 
12  clmdep_msgpack::v2::object::convert<unsigned int>                                                                                      object_fwd.hpp   60  0x55f9eef87ae7 
13  clmdep_msgpack::v1::StdTupleConverter<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>&, 2ul>::convert   tuple.hpp        97  0x55f9eef871b7 
14  clmdep_msgpack::v1::StdTupleConverter<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>&, 3ul>::convert   tuple.hpp        95  0x55f9eef869ea 
15  clmdep_msgpack::v1::StdTupleConverter<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>&, 4ul>::convert   tuple.hpp        95  0x55f9eef860cf 
16  clmdep_msgpack::v1::adaptor::convert<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>, void>::operator() tuple.hpp        126 0x55f9eef852c3 
17  clmdep_msgpack::v1::operator>><std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>>                         adaptor_base.hpp 58  0x55f9eef83793 
18  clmdep_msgpack::v1::object::convert<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>>                    object.hpp       549 0x55f9eef80725 
19  clmdep_msgpack::v2::object::convert<std::tuple<signed char, unsigned int, std::string, clmdep_msgpack::v2::object>>                    object_fwd.hpp   60  0x55f9eef7f129 
20  rpc::detail::dispatcher::dispatch_call

convert_integer_sign is throwing because o.type = clmdep_msgpack::v1::type::STR (5)

[noctice007]

Yeah I'm struggling with this one as well, have you figured it out?

[noctice007]

So with help of my friend I figured out where the error is:
It's in the rpcLip/lib/rpc/dispatcher.cc
Inside dispatch_call():
It calls msg.convert(the_call);, where it throws a type_error exception which is not handled and results the server crash

Just wrap that call inside try catch block to handle that case as you want(respond the type_error to client, stringToInt..)