What happens if you manually run the pg_dump command quoted above against a running 9.1 server, outside of the context of pg_upgrade? (Your port will be probably be different from 50432)
If that still crashes, What if you drop the --binary-upgrade option? The --format=custom option?
I started the 9.1 server normally and ran the above pg_dump (with the appropriate port for that instance).
So it seem the -binary-upgrade option has caused some problem. And the same crash happens regardless of whether i use the 9.1's or 9.3's pg_dump.
If you do the dump using 9.1's pg_dump without --binary-upgrade, and then load that dump file into a new empty 9.1 server, then does it crash if you take a dump against *that* server? If so, would you be allowed to post that dump file?