Re: [syzbot] BUG: corrupted list in netif_napi_add

[Jussi Maki]

On Thu, Oct 14, 2021 at 3:50 PM Paolo Abeni <pabeni@xxxxxxxxxx> wrote:
>
> On Wed, 2021-10-13 at 15:35 +0200, Daniel Borkmann wrote:
> > On 10/13/21 1:40 PM, syzbot wrote:
> > > Hello,
> > >
> > > syzbot found the following issue on:
> >
> > [ +Paolo/Toke wrt veth/XDP, +Jussi wrt bond/XDP, please take a look, thanks! ]
>
> For the records: Toke and me are actively investigating this issue and
> the other recent related one. So far we could not find anything
> relevant.
>
> The onluy note is that the reproducer is not extremelly reliable - I
> could not reproduce locally, and multiple syzbot runs on the same code
> give different results. Anyhow, so far the issue was only observerable
> on a specific 'next' commit which is currently "not reachable" from any
> branch. I'm wondering if the issue was caused by some incosistent
> status of such tree.
>

Hey,

I took a look at the bond/XDP related bits and couldn't find anything
obvious there. And for what it's worth, I was running the syzbot repro
under bpf-next tree (223f903e9c8) in the bpf vmtest.sh environment for
30 minutes without hitting this. An inconsistent tree might be a
plausible cause.