Is the one line configuration actually invalid or should krb5conf handle parsing it? I'm not sure but we should check that out.
Which ever way we handle this a unit test is needed to cover the case.
If we decide that erroring is the right handling we should use an error message that guides the user to why the parsing failed so they can correct the configuration file.
We had a panic problem parsing a config with one line realm configuration, like: [realms] ATHENA.MIT.EDU = { kdc = kerberos.mit.edu }
panic: runtime error: slice bounds out of range [1:0] in config.parseRealms
The following change fixes the panic problem.