Re: [PATCH] wireless: fix 64K kernel heap content leak via ioctl

Jean Tourrilhes
2010-08-27T21:53:42Z

On Fri, Aug 27, 2010 at 02:43:57PM -0700, Kees Cook wrote:
> Hi Jean,
>
> The comment should probably be clarified -- it's the caller's iwp->length
> that may be causing problems

Ha ! I see. It would be for regular iwpoint queries, not for
extended NOMAX queries (scan is a extended NOMAX query).
Note that I don't like the idea of reducing the mallocated
size, especially with regular queries, as I know that some driver may
expect a fixed size in extra and may memcpy to it without double
checking.

> Regardless, the above patch would appear to limit the copy_to_user
> to only the kzalloced region.

I'm glad you like it.

> Thanks!
>
> -Kees

Regards,

Jean