Ok got a scary message today when I tried to git push, a bad object error! Turns out that if you have git lfs (Large File Storage) turned on and you try to push and you are behind the upstream and have LFS changes, then you get this error.
The solution is that you have to do a
git pull --rebase so that the upstream changes are merged and then you can
git push again.
Note that with git lfs, this rebase takes a looooong time