Well, it is "ringing" before the edge because of the propagation skew between the different inverters?
Edit:
But, wait, you don't think it's because of that, do you? That's good because like others that have suggested that, you'd be wrong.
No, you think it's being caused by the scope. Aliasing because, in your opinion, it's a "shitty Chinese scope", right? Well, if that's what you think then you are still wrong.
If that's not what you think, then I'd love to hear what you think it is.