[PATCH v3 57/68] afs: Fix afs_write_end() to handle len > page size

[Linus Torvalds]

On Thu, Dec 16, 2021 at 8:22 AM David Howells <dhowells at redhat.com> wrote:
>
> It is possible for the len argument to afs_write_end() to overrun the end
> of the page (len is used to key the size of the page in afs_write_start()
> when compound pages become a regular thing).

This smells like a bug in the caller.

It's just insane to call "write_end()" with a range that doesn't
actually fit in the page provided.

Exactly how does that happen, and why should AFS deal with it, not
whoever called write_end()?

              Linus