They don't have a mutual defense treaty, sure, but they describe themselves as having a “friendship without limits”. I would agree that China has no interest in getting involved in Putin's idiot war in Ukraine though, and there's zero benefit to China in antagonizing Europe.
What the words are worth in a time of need remains to be seen. Neither side is exactly trustworthy :)
They are absolutely allies, though. Per Putin himself. https://www.reuters.com/world/putin-says-china-is-russias-al...
The CCP are aware of this fact and they're planning for it, but they're not ready yet.
This is what article 9 says: "When a situation arises in which one of the contracting parties deems that peace is being threatened and undermined or its security interests are involved or when it is confronted with the threat of aggression, the contracting parties shall immediately hold contacts and consultations in order to eliminate such threats."