Change session logout to kill only the cookie

Removing the ccache goes too far as it will cause unrelated sessions to
fail as well, this is a problem for accounts used to do unattended
operations and that may operate in parallel.

Fixes https://fedorahosted.org/freeipa/ticket/6682

Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

ipaserver/plugins/session.py

@@ -5,7 +5,6 @@
 from ipalib import Command
 from ipalib.request import context
 from ipalib.plugable import Registry
-from ipaserver.session import logout
 
 register = Registry()
 
@@ -21,7 +20,9 @@ class session_logout(Command):
         ccache_name = getattr(context, 'ccache_name', None)
         if ccache_name is None:
             self.debug('session logout command: no ccache_name found')
+        else:
+            delattr(context, 'ccache_name')
 
-        logout(ccache_name)
+        setattr(context, 'logout_cookie', '')
 
         return dict(result=None)