lua Fix potential event stack OVFL

you could return values in the event callbacks that would never be processed
this would eventually cause a lua stack overflow

settop(0) eats all return values (if any)

Change-Id: Icac6b27e592b385421275d4bd899ed3fe1065669

1 files changed, 3 insertions, 1 deletions

diff --git a/apps/plugins/lua/rocklib_events.c b/apps/plugins/lua/rocklib_events.c
index 1c13a6758f..0cdec20213 100644
--- a/apps/plugins/lua/rocklib_events.c
+++ b/apps/plugins/lua/rocklib_events.c
@@ -253,7 +253,9 @@ static int lua_rev_callback(lua_State *L, struct cb_data *evt)
     lua_pushlightuserdata(L, evt->data);
 
     lua_status = lua_resume(L, 2); /* call the saved function */
-    if (lua_status == LUA_YIELD) /* coroutine.yield() disallowed */
+    if (lua_status == LUA_SUCCESS)
+            lua_settop(L, 0); /* eat any value(s) returned */
+    else if (lua_status == LUA_YIELD) /* coroutine.yield() disallowed */
         luaL_where(L, 1); /* push error string on stack */
 
     return lua_status;