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Date:   Sun, 30 Aug 2020 17:51:33 -0700
From:   Rustam Kovhaev <rkovhaev@gmail.com>
To:     Toshiaki Makita <toshiaki.makita1@gmail.com>
Cc:     davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
        gregkh@linuxfoundation.org
Subject: Re: [PATCH] veth: fix memory leak in veth_newlink()
Message-ID: <20200831005133.GA3295@thinkpad>
References: <20200830131336.275844-1-rkovhaev@gmail.com>
 <32e30526-bcc9-1f2f-1250-f36687561fbb@gmail.com>
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On Mon, Aug 31, 2020 at 09:16:32AM +0900, Toshiaki Makita wrote:
> On 2020/08/30 22:13, Rustam Kovhaev wrote:
> > when register_netdevice(dev) fails we should check whether struct
> > veth_rq has been allocated via ndo_init callback and free it, because,
> > depending on the code path, register_netdevice() might not call
> > priv_destructor() callback
> 
> AFAICS, register_netdevice() always goto err_uninit and calls priv_destructor()
> on failure after ndo_init() succeeded.
> So I could not find such a code path.
> Would you elaborate on it?

in net/core/dev.c:9863, where register_netdevice() calls rollback_registered(),
which does not call priv_destructor(), then register_netdevice() returns error
net/core/dev.c:9884