Re: [PATCH v3 04/22] x86/doublefault: Make memmove() notrace/NOKPROBE

Steven Rostedt
2020-02-19T16:12:33Z

On Wed, 19 Feb 2020 17:04:42 +0100
Peter Zijlstra <peterz@infradead.org> wrote:

> > - memmove(&gpregs->ip, (void *)regs->sp, 5*8);
> > + for (i = 0; i < count; i++) {
> > + int idx = (dst <= src) ? i : count - i;
>
> That's an off-by-one for going backward; 'count - 1 - i' should work
> better, or I should just stop typing for today ;-)

Or, we could just cut and paste the current memmove and make a notrace
version too. Then we don't need to worry bout bugs like this.

-- Steve