I don't share this concern, I've been rebasing frequently(several times a day) for years now and never caused any unrecoverable problems. I would recommend that the last thing you do before pushing a branch you've rebased is

git diff origin/master branch

This way you can see if the diff looks like what you expect it to be. If it doesn't and you believe you messed something up while rebasing just

git reset --hard origin/branch

and redo the rebase