netdev - Re: [syzbot] [net?] possible deadlock in rtnl

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250529091003.3423378b@kernel.org>
Date: Thu, 29 May 2025 09:10:03 -0700
From: Jakub Kicinski <kuba@...nel.org>
To: Stanislav Fomichev <stfomichev@...il.com>
Cc: syzbot <syzbot+846bb38dc67fe62cc733@...kaller.appspotmail.com>,
 davem@...emloft.net, edumazet@...gle.com, horms@...nel.org,
 linux-kernel@...r.kernel.org, netdev@...r.kernel.org, pabeni@...hat.com,
 syzkaller-bugs@...glegroups.com
Subject: Re: [syzbot] [net?] possible deadlock in rtnl_newlink

On Thu, 29 May 2025 08:59:43 -0700 Stanislav Fomichev wrote:
> So this is internal WQ entry lock that is being reordered with rtnl
> lock. But looking at process_one_work, I don't see actual locks, mostly
> lock_map_acquire/lock_map_release calls to enforce some internal WQ
> invariants. Not sure what to do with it, will try to read more.

Basically a flush_work() happens while holding rtnl_lock,
but the work itself takes that lock. It's a driver bug.