Possible race condition in TopicInfo

[iche033]

Environment

• OS Version: 22.04
• Source or binary build? source build, harmonic

Description

• Expected behavior: Gazebo GUI plugins should be able to query topic info
• Actual behavior: Gazebo GUI plugins crash when querying topic info

Steps to reproduce

1. Launch Gazebo and repeatedly open and close a gui plugin that uses the ToipcInfo API, .e.g TopicViewer or Image Display

Eventually the gazebo GUI will crash. For me, this happens within 5 tries.

Output

(gdb) bt
#0  0x00007fffe0009690 in  ()
#1  0x00007ffff27666a0 in std::_Destroy<gz::transport::v13::MessagePublisher>(gz::transport::v13::MessagePublisher*) (__pointer=0x7fffe0009580) at /usr/include/c++/11/bits/stl_construct.h:151
#2  std::_Destroy_aux<false>::__destroy<gz::transport::v13::MessagePublisher*>(gz::transport::v13::MessagePublisher*, gz::transport::v13::MessagePublisher*)
    (__last=<optimized out>, __first=0x7fffe0009580) at /usr/include/c++/11/bits/stl_construct.h:163
#3  std::_Destroy<gz::transport::v13::MessagePublisher*>(gz::transport::v13::MessagePublisher*, gz::transport::v13::MessagePublisher*) (__last=<optimized out>, __first=<optimized out>)
    at /usr/include/c++/11/bits/stl_construct.h:196
#4  std::_Destroy<gz::transport::v13::MessagePublisher*, gz::transport::v13::MessagePublisher>(gz::transport::v13::MessagePublisher*, gz::transport::v13::MessagePublisher*, std::allocator<gz::transport::v13::MessagePublisher>&) (__last=<optimized out>, __first=<optimized out>) at /usr/include/c++/11/bits/alloc_traits.h:848
#5  std::vector<gz::transport::v13::MessagePublisher, std::allocator<gz::transport::v13::MessagePublisher> >::_M_realloc_insert<gz::transport::v13::MessagePublisher>(__gnu_cxx::__normal_iterator<gz::transport::v13::MessagePublisher*, std::vector<gz::transport::v13::MessagePublisher, std::allocator<gz::transport::v13::MessagePublisher> > >, gz::transport::v13::MessagePublisher&&)
   
       (this=0x7fffe0009500, __position={<gz::transport::v13::Publisher> = {_vptr.Publisher = 0x100, topic = "", addr = "", pUuid = "", nUuid = "", opts = {_vptr.AdvertiseOptions = 0x0, dataPtr = std::unique_ptr<gz::transport::v13::AdvertiseOptionsPrivate> = {get() = 0x0}}}, ctrl = "", msgTypeName = "", msgOpts = {<gz::transport::v13::AdvertiseOptions> = {_vptr.AdvertiseOptions = 0x0, dataPtr = std::unique_ptr<gz::transport::v13::AdvertiseOptionsPrivate> = {get() = 0x0}}, dataPtr = std::unique_ptr<gz::transport::v13::AdvertiseMessageOptionsPrivate> = {get() = 0x0}}}) at /usr/include/c++/11/bits/vector.tcc:498
#6  0x00007ffff2768298 in std::vector<gz::transport::v13::MessagePublisher, std::allocator<gz::transport::v13::MessagePublisher> >::emplace_back<gz::transport::v13::MessagePublisher>(gz::transport::v13::MessagePublisher&&) (this=0x7fffe0009500) at /usr/include/c++/11/bits/vector.tcc:121
#7  std::vector<gz::transport::v13::MessagePublisher, std::allocator<gz::transport::v13::MessagePublisher> >::push_back(gz::transport::v13::MessagePublisher&&) (__x=..., this=0x7fffe0009500)
    at /usr/include/c++/11/bits/stl_vector.h:1204
#8  gz::transport::v13::TopicStorage<gz::transport::v13::MessagePublisher>::AddPublisher(gz::transport::v13::MessagePublisher const&) (this=this@entry=0x555555a8bb20, _publisher=...)
    at /home/ian/code/gz_h_ws/src/gz-transport/include/gz/transport/TopicStorage.hh:82
#9  0x00007ffff278a42f in gz::transport::v13::Discovery<gz::transport::v13::MessagePublisher>::DispatchDiscoveryMsg(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, char*, unsigned short)
    (this=this@entry=0x555555a8b9b0, _fromIp="172.17.0.1", _msg=_msg@entry=0x7fffeac53dd2 "\020\n\032$22e468c1-90ef-47dc-9de7-0ff52c8b0b3d \t:\256\001\n*@/injera:ian@/world/ModelTest/light_config\022\026tcp://172.17.0.1:38041\032$22e468c1-90ef-47dc-9de7-0ff52c8b0b3d\"$906fe6cb-ef51-4f1e-9db0-c6c04fd57b75(\002\062\032\022\rgz.ms"..., _len=_len@entry=219)
    at /home/ian/code/gz_h_ws/src/gz-transport/include/gz/transport/Discovery.hh:1078
#10 0x00007ffff278af38 in gz::transport::v13::Discovery<gz::transport::v13::MessagePublisher>::RecvDiscoveryUpdate() (this=0x555555a8b9b0)
    at /home/ian/code/gz_h_ws/src/gz-transport/include/gz/transport/Discovery.hh:900
#11 0x00007ffff278b068 in gz::transport::v13::Discovery<gz::transport::v13::MessagePublisher>::RecvMessages() (this=0x555555a8b9b0)
    at /home/ian/code/gz_h_ws/src/gz-transport/include/gz/transport/Discovery.hh:832
#12 0x00007ffff3af02b3 in  () at /lib/x86_64-linux-gnu/libstdc++.so.6
#13 0x00007ffff7a83b43 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#14 0x00007ffff7b15a00 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

[caguero]

@iche033, I was able to reproduce the problem. I think there are two separate issues:

The crash with Image Display looks an issue in Transport. I created a fix in #432 .

The crash with Topic Viewer seems different, as I think there's an additional issue in the TopicViewer plugin. I'll create a separate fix for that. See gazebosim/gz-gui#566.