Update SSHD to include SSHD-28 (deadlock on close) bugfix

This custom version of sshd-core includes a bug fix patch I proposed
in https://issues.apache.org/jira/browse/SSHD-28 to fix a deadlock
between the NioProcessor and the application threads.

If the NioProcessor deadlocks, it is unable to perform any additional
IO operations.  Any connection which is assigned to the deadlocked
NioProcessor is hosed... and is unable to perform an network IO.
Since the NioProcessors are assigned round-robin, and the number
of them in the pool is based on load, its possible to sometimes
get a good NioProcessor, and other times to get the deadlocked one.

I've been running this custom sshd-core build on all of my own
production servers for over a week, and its cleared up the deadlock,
so it seems suitable for inclusion in a release.  Unfortunately it
has not yet been committed to the MINA SSHD repository.

Signed-off-by: Shawn O. Pearce <sop@google.com>
1 file changed