Re: [syzbot] BUG: corrupted list in netif_napi_add

On Thu, Oct 14, 2021 at 3:50 PM Paolo Abeni [off-list ref] wrote:

On Wed, 2021-10-13 at 15:35 +0200, Daniel Borkmann wrote:

quoted

On 10/13/21 1:40 PM, syzbot wrote:

quoted

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.