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Date: Wed, 10 Sep 2025 18:09:06 +0100
From: Simon Horman <horms@kernel.org>
To: Hangbin Liu <liuhangbin@gmail.com>
Cc: netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	MD Danish Anwar <danishanwar@ti.com>,
	Alexander Lobakin <aleksander.lobakin@intel.com>,
	Jaakko Karrenpalo <jkarrenpalo@gmail.com>,
	Fernando Fernandez Mancera <ffmancera@riseup.net>,
	Murali Karicheri <m-karicheri2@ti.com>,
	WingMan Kwok <w-kwok2@ti.com>, Stanislav Fomichev <sdf@fomichev.me>,
	Xiao Liang <shaw.leon@gmail.com>,
	Kuniyuki Iwashima <kuniyu@google.com>,
	Johannes Berg <johannes.berg@intel.com>
Subject: Re: [PATCHv3 net 3/3] hsr: hold rcu and dev lock for
 hsr_get_port_ndev
Message-ID: <20250910170906.GD30363@horms.kernel.org>
References: <20250905091533.377443-1-liuhangbin@gmail.com>
 <20250905091533.377443-4-liuhangbin@gmail.com>
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In-Reply-To: <20250905091533.377443-4-liuhangbin@gmail.com>

On Fri, Sep 05, 2025 at 09:15:33AM +0000, Hangbin Liu wrote:
> hsr_get_port_ndev calls hsr_for_each_port, which need to hold rcu lock.
> On the other hand, before return the port device, we need to hold the
> device reference to avoid UaF in the caller function.
> 
> Suggested-by: Paolo Abeni <pabeni@redhat.com>
> Fixes: 9c10dd8eed74 ("net: hsr: Create and export hsr_get_port_ndev()")
> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>

Thanks.

I agree with your analysis.
And I see that this addresses Paolo's review over v2.

Reviewed-by: Simon Horman <horms@kernel.org>