Re: [syzbot] [net?] WARNING in ethnl_req_get_phydev

[Maxime Chevallier]

Hello,

On Mon, 26 Aug 2024 01:50:24 -0700
syzbot <syzbot+ec369e6d58e210135f71@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    f9db28bb09f4 Merge branch 'net-redundant-judgments'
> git tree:       net-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=1051fa7b980000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=df2f0ed7e30a639d
> dashboard link: https://syzkaller.appspot.com/bug?extid=ec369e6d58e210135f71
> compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=113da825980000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10d5f229980000
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/585e02f7fe7b/disk-f9db28bb.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/b9faf5d24900/vmlinux-f9db28bb.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/f9df5868ea4f/bzImage-f9db28bb.xz
> 
> The issue was bisected to:
> 
> commit 31748765bed3fb7cebf4a32b43a6fdf91b9c23de
> Author: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>
> Date:   Wed Aug 21 15:10:04 2024 +0000
> 
>     net: ethtool: pse-pd: Target the command to the requested PHY
> 
> bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=13d09047980000
> final oops:     https://syzkaller.appspot.com/x/report.txt?x=10309047980000
> console output: https://syzkaller.appspot.com/x/log.txt?x=17d09047980000

Looks also like this is triggered because the validate callback doesn't
run under rtnl() as I wrongly assumed. I'll look into it.

Thanks,

Maxime