lua smtp: fix SMTPGetMimeField arg checking

Properly check argument before passing it on: CID 1363385: (NULL_RETURNS)

diff --git a/src/util-lua-smtp.c b/src/util-lua-smtp.c
index f18bea1b3c782b971cd4b5c806a186574f14209a..a64c7098323ebfa3204ca7d58908cab8d92230a4 100644 (file)
--- a/src/util-lua-smtp.c
+++ b/src/util-lua-smtp.c
@@ -112,6 +112,9 @@ static int SMTPGetMimeField(lua_State *luastate)
         return LuaCallbackError(luastate, "Error: no flow found");
     }
     const char *name = LuaGetStringArgument(luastate, 1);
+    if (name == NULL)
+        return LuaCallbackError(luastate, "1st argument missing, empty or wrong type");
+
     /* lock check */
     if(lock_hint == LUA_FLOW_NOT_LOCKED_BY_PARENT) {
         FLOWLOCK_RDLOCK(flow);