Re: [PATCH] usercopy: Disable CONFIG_HARDENED_USERCOPY_PAGESPAN

[Christoph Hellwig]

On Thu, Mar 24, 2022 at 04:02:55PM -0700, Kees Cook wrote:
> CONFIG_HARDENED_USERCOPY_PAGESPAN has been mostly broken for a while,
> and it has become hard to ignore with some recent scsi changes[1].
> While there is a more complete series to replace it with better checks[2],
> it should have more soak time in -next. Instead, disable the config now,
> with the expectation that it will be fully replaced in the next kernel
> release.
> 
> [1] https://lore.kernel.org/lkml/20220324064846.GA12961@xxxxxx/
> [2] https://lore.kernel.org/linux-hardening/20220110231530.665970-1-willy@xxxxxxxxxxxxx/
> 
> Suggested-by: Christoph Hellwig <hch@xxxxxx>
> Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

I'd prefer to just remove the code, but this is better than nothing:

Acked-by: Christoph Hellwig <hch@xxxxxx>