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Message-ID: <0a568e890497f4066128b1ce957904e0c5540c16.camel@redhat.com>
Subject: Re: [PATCH net] sfc: fix potential memleak in
 __ef100_hard_start_xmit()
From:   Paolo Abeni <pabeni@redhat.com>
To:     Leon Romanovsky <leon@kernel.org>,
        Zhang Changzhong <zhangchangzhong@huawei.com>,
        Edward Cree <ecree.xilinx@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Tue, 22 Nov 2022 09:28:42 +0100
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References: <1668671409-10909-1-git-send-email-zhangchangzhong@huawei.com>
         <Y3YctdnKDDvikQcl@unreal> <efedaa0e-33ce-24c6-bb9d-8f9b5c4a1c38@huawei.com>
         <Y3YxlxPIiw43QiKE@unreal> <Y3dNP6iEj2YyEwqJ@gmail.com>
         <Y3e8wEZme3OpMZKV@unreal>
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Hello,

On Fri, 2022-11-18 at 19:11 +0200, Leon Romanovsky wrote:
> On Fri, Nov 18, 2022 at 09:15:43AM +0000, Martin Habets wrote:
> > On Thu, Nov 17, 2022 at 03:05:27PM +0200, Leon Romanovsky wrote:
> > > Please take a look __ef100_enqueue_skb() and see if it frees SKB on
> > > error or not. If not, please fix it.
> > 
> > That function looks ok to me, but I appreciate the extra eyes on it.
> 
> __ef100_enqueue_skb() has the following check in error path:
> 
>   498 err:
>   499         efx_enqueue_unwind(tx_queue, old_insert_count);
>   500         if (!IS_ERR_OR_NULL(skb))
>   501                 dev_kfree_skb_any(skb);
>   502
> 
> The issue is that skb is never error or null here and this "if" is
> actually always true and can be deleted.

I think that such additional change could be suite for a different net-
next patch, while this -net patch could land as is, @Leon: do you
agree?

Thanks!

Paolo