Re: INFO: rcu detected stall in xfrm_confirm_neigh

From: Steffen Klassert
Date: Mon Feb 19 2018 - 02:23:13 EST


On Tue, Feb 13, 2018 at 10:19:17AM +0100, Dmitry Vyukov wrote:
> On Mon, Feb 12, 2018 at 4:26 PM, Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
> > On Mon, Feb 12, 2018 at 4:23 PM, syzbot
> > <syzbot+7d03c810e50aaedef98a@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> >> Hello,
> >>
> >> syzbot hit the following crash on net-next commit
> >> 9515a2e082f91457db0ecff4b65371d0fb5d9aad (Thu Jan 25 03:37:38 2018 +0000)
> >> net/ipv4: Allow send to local broadcast from a socket bound to a VRF
> >>
> >> So far this crash happened 6 times on net-next.
> >> Unfortunately, I don't have any reproducer for this crash yet.
> >> Raw console output is attached.
> >> compiler: gcc (GCC) 7.1.1 20170620
> >> .config is attached.
> >
> >
> > +xfrm maintainers
>
> Here is a C repro:
> https://gist.githubusercontent.com/dvyukov/92c67ba9afaaa960bcfbdc6ef549ac10/raw/786f9221c1d707c7f4a15effcb1d5997dd4f8638/gistfile1.txt

Seems like syzbot does not know about this reproducer.

I've send a patch to test and got this as the reply:

This crash does not have a reproducer. I cannot test it.