Re: [PATCH] aio: fix a user triggered use after free (and fix freeze protection of aio writes)

[Linus Torvalds]

On Sat, Oct 29, 2016 at 12:17 PM, Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
>
> AFAICS, the possibility of dropping the last reference to struct file
> before ->write_iter() has returned is fundamentally broken.  I might be
> missing something subtle here, but...

Ok, let's add a get_file(); fput(); around that whole iter call sequence.

And that's a separate issue from "we should hold the fs freezer lock
around the whole operation". So I think we need both.

Does that make everybody happy?

              Linus