Merge tag 'rxrpc-fixes-20191220' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

David Howells says:

====================
rxrpc: Fixes

Here are a couple of bugfixes plus a patch that makes one of the bugfixes
easier:

 (1) Move the ping and mutex unlock on a new call from rxrpc_input_packet()
     into rxrpc_new_incoming_call(), which it calls.  This means the
     lock-unlock section is entirely within the latter function.  This
     simplifies patch (2).

 (2) Don't take the call->user_mutex at all in the softirq path.  Mutexes
     aren't allowed to be taken or released there and a patch was merged
     that caused a warning to be emitted every time this happened.  Looking
     at the code again, it looks like that taking the mutex isn't actually
     necessary, as the value of call->state will block access to the call.

 (3) Fix the incoming call path to check incoming calls earlier to reject
     calls to RPC services for which we don't have a security key of the
     appropriate...