ovl: pass original credentials, not mounter credentials during create

ovl: pass original credentials, not mounter credentials during create

When creating new files the security layer expects the original
credentials to be passed.  When cleaning up the code this was accidently
changed to pass the mounter's credentials by relying on current->cred
which is already overriden at this point.  Pass the original credentials
directly.

Reported-by: Ondrej Mosnacek <omosnace@redhat.com>
Reported-by: Paul Moore <paul@paul-moore.com>
Fixes: e566bff96322 ("ovl: port ovl_create_or_link() to new ovl_override_creator_creds")
Link: https://lore.kernel.org/CAFqZXNvL1ciLXMhHrnoyBmQu1PAApH41LkSWEhrcvzAAbFij8Q@mail.gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Tested-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>