Re: [syzbot] [net?] [bpf?] possible deadlock in xsk_diag_dump
From: Jakub Kicinski
Date: Fri Apr 11 2025 - 18:38:44 EST
On Tue, 08 Apr 2025 04:53:35 -0700 syzbot wrote:
> Chain exists of:
> &xs->mutex --> &rdev->wiphy.mtx --> &net->xdp.lock
>
> Possible unsafe locking scenario:
>
> CPU0 CPU1
> ---- ----
> lock(&net->xdp.lock);
> lock(&rdev->wiphy.mtx);
> lock(&net->xdp.lock);
> lock(&xs->mutex);
After looking at it with Stanislav our best guess is that we're mixing
normal and ops locked devices in close_many. Will send a fix over the
weekend.