When the new dur_passthrough test runs with option 8, it gets to max_message_size.js and then gets a SIGPIPE:

Tue Jan 22 02:14:06.411 mongo got signal SIGPIPE

Apparently, this then orphans the running mongod, and then smoke.py treats the test as successful and moves on to the next test in the 'dur' suite.
This then causes all the other builds on this builder to fail (including the 2.2 build) because port 32100 is in use.