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Message-ID: <fe5947e2-8a91-48f5-9037-f3a48b55fbd6@kernel.org>
Date: Tue, 18 Mar 2025 20:08:50 -0600
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Subject: Re: [PATCH net] net: fix NULL pointer dereference in l3mdev_l3_rcv
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To: Wang Liang <wangliang74@huawei.com>, Simon Horman <horms@kernel.org>
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
 pabeni@redhat.com, fw@strlen.de, daniel@iogearbox.net,
 yuehaibing@huawei.com, zhangchangzhong@huawei.com, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
References: <20250313012713.748006-1-wangliang74@huawei.com>
 <20250318143800.GA688833@kernel.org>
 <e8da7ce4-c76c-488e-80cb-dff95bf00fe0@kernel.org>
 <94a34aa3-a823-4550-b16a-179e6f6d6292@huawei.com>
From: David Ahern <dsahern@kernel.org>
In-Reply-To: <94a34aa3-a823-4550-b16a-179e6f6d6292@huawei.com>
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On 3/18/25 3:07 AM, Wang Liang wrote:
>>> It seems to me that checking master->l3mdev_ops like this is racy.
>> vrf device leaves the l3mdev ops set; that is probably the better way
>> to go.
> 
> Thanks.
> 
> Only l3s ipvlan set the dev->l3mdev_ops to NULL at present, I will delete
> 'dev->l3mdev_ops = NULL' in ipvlan_l3s_unregister(), is that ok?
> 

I think that avoids the race you saw. vrf has had the ops for 9 years or
so and not seen that problem.