From: Matthias Gerstner <matthias.gerstner@suse.de>
Date: Fri, 14 Jul 2017 14:23:05 +0200
Subject: fixed local DoS when UnregisterHandler was called for a not existing
 handler
Git-commit: e2d953050766ac538615a811c64b34358614edce
References: bsc#1049488

Any user with DBUS access could cause a SEGFAULT in tcmu-runner by
running something like this:

dbus-send --system --print-reply --dest=org.kernel.TCMUService1 /org/kernel/TCMUService1/HandlerManager1 org.kernel.TCMUService1.HandlerManager1.UnregisterHandler string:123

Acked-by: Lee Duncan <lduncan@suse.com>
---
 main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/main.c
+++ b/main.c
@@ -592,7 +592,7 @@ on_unregister_handler(TCMUService1Handle
 		      gpointer user_data)
 {
 	struct tcmur_handler *handler = find_handler_by_subtype(subtype);
-	struct dbus_info *info = handler->opaque;
+	struct dbus_info *info = handler ? handler->opaque : NULL;
 
 	if (!handler) {
 		g_dbus_method_invocation_return_value(invocation,