CInv::GetCommand(): type=1373179482 unknown type #9110

It seems that bitcoin{d,-qt} can be crashed by being sent an inv of an unknown type. At least, it caused mine to:-

2016-11-08 00:45:36.470 ProcessMessages(getdata, 397 bytes): CHECKSUM ERROR expected=6d9dbcdf was=a1046737 peer=39585
2016-11-08 00:45:36.481 

************************
EXCEPTION: St12out_of_range       
CInv::GetCommand(): type=1373179482 unknown type       
bitcoin in ProcessMessages()       

2016-11-08 00:45:36.482 ProcessMessages(getdata, 397 bytes) FAILED peer=39585
2016-11-08 00:45:36.487 

************************
EXCEPTION: St12out_of_range       
CInv::GetCommand(): type=1373179482 unknown type       
bitcoin in msghand       

If the throw std::out_of_range(strprintf("CInv::GetCommand(): type=%d unknown type", type)); in protocol.cpp supposed to cause the program to end?

I'm able to reproduce this error in the log by enabling debug=net and sending an invalid inv type:

2016-11-09 09:40:27 

************************
EXCEPTION: St12out_of_range       
CInv::GetCommand(): type=666 unknown type       
bitcoin in ProcessMessages()       

2016-11-09 09:40:27 ProcessMessages(inv, 37 bytes) FAILED peer=7

However the exception is caught and printed, the process does not crash. It also appears without debug=net.

Having a ToString function raise an exception is kind of unexpected. I think we should change CInv::ToString to catch the exception and return something like unknown: %d instead, for better troubleshooting. But it does not result in a crash right now.

@rebroad: so what "to cause the program to end?"? Was it some local change on your side? Did bitcoind really stopped at all?