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Message-ID: <4127e24d-e78c-40da-80b7-96d3e789c489@kylinos.cn>
Date: Mon, 15 Jan 2024 15:28:03 +0800
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Subject: Re: [PATCH net] net: phy: Fix possible NULL pointer dereference
 issues caused by phy_attached_info_irq
Content-Language: en-US
To: Andrew Lunn <andrew@lunn.ch>
Cc: hkallweit1@gmail.com, linux@armlinux.org.uk, davem@davemloft.net,
 edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
 f.fainelli@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20240112095724.154197-1-chentao@kylinos.cn>
 <627c9558-04df-43a6-b6e4-a13f24a8bc1d@lunn.ch>
 <b71c5e28-2dbe-48c8-ab92-e1dad9d6f2e4@kylinos.cn>
 <bd80fc69-d334-4b69-8ba3-3b2b86e1fd84@lunn.ch>
From: Kunwu Chan <chentao@kylinos.cn>
In-Reply-To: <bd80fc69-d334-4b69-8ba3-3b2b86e1fd84@lunn.ch>
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On 2024/1/15 11:45, Andrew Lunn wrote:
>>> Here, i would just skip the print and continue with the reset of the
>>> function. The print is just useful information, its not a big problem
>>> if its not printed. However, if this function does not complete, the
>>> network interface is likely to be dead.
>> Thanks for the reminder.
>> The second part doesn't look so perfect, can we just print an empty string
>> when the irq_str is empty?
>>
>> --- a/drivers/net/phy/phylink.c
>> +++ b/drivers/net/phy/phylink.c
>> @@ -1886,7 +1886,7 @@ static int phylink_bringup_phy(struct phylink *pl,
>> struct phy_device *phy,
>>          irq_str = phy_attached_info_irq(phy);
>>          phylink_info(pl,
>>                       "PHY [%s] driver [%s] (irq=%s)\n",
>> -                    dev_name(&phy->mdio.dev), phy->drv->name, irq_str);
>> +                    dev_name(&phy->mdio.dev), phy->drv->name, irq_str ?
>> irq_str : "");
>>          kfree(irq_str);
> 
> That is O.K, or skip the whole phylink_info().
> 
>       Andrew

Thanks, I will update it in v2 patch. Personal view, print a msg is good 
for debug.
-- 
Thanks,
   Kunwu