According to comments in main/pbx.c, it is essential that if we are going to lock

the conlock as well as the hints lock, it must be locked in that respective order.
In order to prevent a potential deadlock, we need to lock the conlock prior to 
locking the hints lock in ast_hint_state_changed (see the call stack example on
issue #11323 for how this can happen).

(closes issue #11323, reported  by eelcob, suggestion for patch by eelcob, patch by me)



git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@89457 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/pbx.c

@@ -2002,6 +2002,7 @@ void ast_hint_state_changed(const char *device)
 {
 	struct ast_hint *hint;
 
+	ast_mutex_lock(&conlock);
 	AST_LIST_LOCK(&hints);
 
 	AST_LIST_TRAVERSE(&hints, hint, list) {
@@ -2039,6 +2040,7 @@ void ast_hint_state_changed(const char *device)
 	}
 
 	AST_LIST_UNLOCK(&hints);
+	ast_mutex_unlock(&conlock);
 }
 
 /*! \brief  ast_extension_state_add: Add watcher for extension states */