So I have this issue, I expreinced it a few times. As you can see on the picture Photoshop does this weird thing - sometimes when I copy paste an image into a PSD file it either stamps one segment of the copied image all over the layers (literally...riuns all of my layers) or cuts squares into them. I tried to roll it back, does not seems to work. It happens very randomly.
My photoshop is not updated to the newest version, could it be the problem? Has anyone came across this type of glitch with any versions of PS?
Can you try going to Preferences > Technology Previews and check Deactivate Native Canvas. Then restart Photoshop and see if you still encounter the issue - will try this, see if it works. So far only happaned twice, but both in the past 3 weeks. PS has been updated to its latest version, maybe that was the issue (at least I hope).