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    SubjectRe: [PATCH v2 10/19] ipv4: prevent bounds-check bypass via speculative execution
    On Fri, Jan 12, 2018 at 10:47:44AM -0800, Dan Williams wrote:
    > On Thu, Jan 11, 2018 at 11:59 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
    > >> Cc: "David S. Miller" <davem@davemloft.net>
    > >> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
    > >> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
    > >> Cc: netdev@vger.kernel.org
    > >> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
    > >> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
    > >> ---
    > >> net/ipv4/raw.c | 10 ++++++----
    > >> 1 file changed, 6 insertions(+), 4 deletions(-)
    > >
    > > Ugh, what is this, the 4th time I've said "I don't think this is an
    > > issue, so why are you changing this code." to this patch. To be
    > > followed by a "oh yeah, you are right, I'll drop it", only to see it
    > > show back up in the next time this patch series is sent out?
    > >
    > > Same for the other patches in this series that I have reviewed 4, maybe
    > > 5, times already. The "v2" is not very true here...
    >
    > The theme of the review feedback on v1 was 'don't put ifence in any
    > net/ code', and that was addressed.
    >
    > I honestly thought the new definition of array_ptr() changed the
    > calculus on this patch. Given the same pattern appears in the ipv6
    > case, and I have yet to hear that we should drop the ipv6 patch, make
    > the code symmetric just for readability purposes. Otherwise we need a
    > comment saying why this is safe for ipv4, but maybe not safe for ipv6,
    > I think 'array_ptr' is effectively that comment. I.e. 'array_ptr()' is
    > designed to be low impact for instrumenting false positives. If that
    > new argument does not hold water I will definitely drop this patch.

    I also argued, again in an older review of this same patch series, that
    the ipv6 patch should be dropped as well for this same exact reason.

    I didn't think you wanted to hear me rant about the same thing on both
    patches :)

    greg k-h

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