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From: Jakub Kicinski <kuba@kernel.org>
To: Qingfang Deng <qingfang.deng@linux.dev>
Cc: Minhong He <heminhong@kylinos.cn>,
	Andrew Lunn <andrew+netdev@lunn.ch>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Paolo Abeni <pabeni@redhat.com>,
	netdev@vger.kernel.org, Kees Cook <kees@kernel.org>,
	Eric Woudstra <ericwouds@gmail.com>, Felix Fietkau <nbd@nbd.name>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: pppoe: check register_netdevice_notifier() error in pppoe_init()
Date: Tue, 4 Aug 2026 18:52:41 -0700	[thread overview]
Message-ID: <20260804185241.605ec90c@kernel.org> (raw)
In-Reply-To: <fca5745a-dfa4-4e90-99fb-483536c94591@linux.dev>

On Tue, 4 Aug 2026 22:20:53 +0800 Qingfang Deng wrote:
> >> +    err = register_netdevice_notifier(&pppoe_notifier);
> >> +    if (err)
> >> +        goto out_unregister_packs;  
> > 
> > You can move the registration above the dev_add_offload(), so that the 
> > unwind path is cleaner.
> >   
> 
> AI-review found a use-after-free. To avoid that, this needs to be placed 
> between register_pernet_device() and proto_register().

SG, but please note that register_netdevice_notifier()
cannot actually fail unless the notifier that's getting
registered fails.

Please do not add the Fixes tag, re-target this at net-next
and add something like:

   This is a future looking check, register_netdevice_notifier()
   only fails on double registration or if the registered notifier
   itself returns an error.

to the commit msg

      reply	other threads:[~2026-08-05  1:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-03  8:59 [PATCH net] net: pppoe: check register_netdevice_notifier() error in pppoe_init() Minhong He
2026-08-04  8:28 ` Qingfang Deng
2026-08-04 14:20   ` Qingfang Deng
2026-08-05  1:52     ` Jakub Kicinski [this message]

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