Don't attempt a websocket protocol removal if res_http_websocket isn't there

This patch sets the protocols container provided by res_http_websocket to NULL
when the module gets unloaded and adds the necessary checks when adding/
removing a websocket protocol. This prevents some FRACKing on an invalid
pointer to the disposed container if a module that uses res_http_websocket is
unloaded after it.



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@384942 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 9 insertions, 0 deletions

diff --git a/res/res_http_websocket.c b/res/res_http_websocket.c
index cfc6d16f5..15ff8fa45 100644
--- a/res/res_http_websocket.c
+++ b/res/res_http_websocket.c
@@ -122,6 +122,10 @@ int AST_OPTIONAL_API_NAME(ast_websocket_add_protocol)(const char *name, ast_webs
 {
 	struct websocket_protocol *protocol;
 
+	if (!protocols) {
+		return -1;
+	}
+
 	ao2_lock(protocols);
 
 	/* Ensure a second protocol handler is not registered for the same protocol */
@@ -157,6 +161,10 @@ int AST_OPTIONAL_API_NAME(ast_websocket_remove_protocol)(const char *name, ast_w
 {
 	struct websocket_protocol *protocol;
 
+	if (!protocols) {
+		return -1;
+	}
+
 	if (!(protocol = ao2_find(protocols, name, OBJ_KEY))) {
 		return -1;
 	}
@@ -670,6 +678,7 @@ static int unload_module(void)
 	ast_websocket_remove_protocol("echo", websocket_echo_callback);
 	ast_http_uri_unlink(&websocketuri);
 	ao2_ref(protocols, -1);
+	protocols = NULL;
 
 	return 0;
 }