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

From: Alan Cox
Date: Sat Jan 06 2018 - 07:24:51 EST


On Sat, 6 Jan 2018 10:01:54 +0100
Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> 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.

Alan