Re: [PATCH 14/18] ipv4: prevent bounds-check bypass via speculative execution

Greg KH
2018-01-06T15:14:24Z

On Sat, Jan 06, 2018 at 12:23:47PM +0000, Alan Cox wrote:
> On Sat, 6 Jan 2018 10:01:54 +0100
> Greg KH <gregkh@linuxfoundation.org> wrote:
>
> > On Fri, Jan 05, 2018 at 05:11:10PM -0800, Dan Williams wrote:
> > > Static analysis reports that 'offset' may be a user controlled value
> >
> > Can I see the rule that determined that? It does not feel like that is
> > correct, given the 3+ levels deep that this function gets this value
> > from...
>
> On a current x86 you can execute something upwards of 150 instructions in
> a speculation window.

Yeah, I agree, it's deep :(

But for this patch, I thought the prior review determined that it was
not a problem. Was that somehow proven incorrect?

thanks,

greg k-h