Re: [PATCH v4] bpf: Fix KASAN use-after-free Read in compute_effective_progs

[Andrii Nakryiko]

On Thu, Jun 2, 2022 at 7:37 AM Tadeusz Struk <tadeusz.struk@xxxxxxxxxx> wrote:
>
> Hi Andrii,
> On 5/23/22 15:47, Andrii Nakryiko wrote:
> >> Hi Andrii,
> >> Do you have any more feedback? Does it look better to you now?
> > Hi, this is on my TODO list, but I need a bit more focused time to
> > think all this through and I haven't managed to get it in last week.
> > I'm worried about the percpu_ref_is_zero(&desc->bpf.refcnt) portion
> > and whether it can cause some skew in the calculated array index, I
> > need to look at this a bit more in depth. Sorry for the delay.
>
> Did you get a chance to look at this yet?
>

Hm.. I've applied it two days ago, but for some reason there was no
notification from the bot. It's now c89c79fda9b6 ("bpf: Fix KASAN
use-after-free Read in compute_effective_progs").

> --
> Thanks,
> Tadeusz