Re: [PATCH 02/11] fs: don't allow kernel reads and writes without iter ops
From: Kees Cook
Date: Tue Aug 18 2020 - 15:34:31 EST
On Mon, Aug 17, 2020 at 09:32:03AM +0200, Christoph Hellwig wrote:
> Don't allow calling ->read or ->write with set_fs as a preparation for
> killing off set_fs. All the instances that we use kernel_read/write on
> are using the iter ops already.
>
> If a file has both the regular ->read/->write methods and the iter
> variants those could have different semantics for messed up enough
> drivers. Also fails the kernel access to them in that case.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
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Kees Cook