Re: [PATCH] vfs: fix statfs64() returning impossible EOVERFLOW for 64-bit f_files

[Linus Torvalds]

On Mon, Aug 6, 2018 at 10:06 AM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
>
> That leaves us with f_bsize and f_frsize (the latter defaulting to the former).
> Hugetlbfs can put greater than 4Gb values in there, for really huge pages.
> And that's the only thing worth checking in there.
>
> So the whole put_compat_statfs64() thing should be

Ack, I'm ok with this simplification.

> I'm somewhat tempted to get rid of those 'long' in struct kstatfs,

I'm ok with this one too.

> with
>
> #define STATFS_COPYOUT(type)                                            \
> static int put##type(struct kstatfs *st, struct type __user *p)         \

No. Don't do this.

I'm ok with the #define to avoid duplication, but don't bother with
the FIT_IN() after you've above successfully argued that it's
pointless for anything but f_bsize/frsize.

So if you do the macro to generate the different copyout versions,
just use your simplified code for that macro instead. With FIT_IN()
just for f_bsize/frsize.

                    Linus