Re: [PATCH] net: phy: phy_led_triggers: Fix a possible null-pointer dereference in phy_led_trigger_change_speed()

[David Miller <davem@davemloft.net>]

From: Andrew Lunn <andrew@lunn.ch>
Date: Tue, 30 Jul 2019 05:32:29 +0200

> On Tue, Jul 30, 2019 at 10:25:36AM +0800, Jia-Ju Bai wrote:
>> 
>> 
>> On 2019/7/29 21:45, Andrew Lunn wrote:
>> >On Mon, Jul 29, 2019 at 05:24:24PM +0800, Jia-Ju Bai wrote:
>> >>In phy_led_trigger_change_speed(), there is an if statement on line 48
>> >>to check whether phy->last_triggered is NULL:
>> >>     if (!phy->last_triggered)
>> >>
>> >>When phy->last_triggered is NULL, it is used on line 52:
>> >>     led_trigger_event(&phy->last_triggered->trigger, LED_OFF);
>> >>
>> >>Thus, a possible null-pointer dereference may occur.
>> >>
>> >>To fix this bug, led_trigger_event(&phy->last_triggered->trigger,
>> >>LED_OFF) is called when phy->last_triggered is not NULL.
>> >>
>> >>This bug is found by a static analysis tool STCheck written by us.
>> >Who is 'us'?
>> 
>> Me and my colleague...
> 
> Well, we can leave it very vague, giving no idea who 'us' is. But
> often you want to name the company behind it, or the university, or
> the sponsor, etc.

I agree, if you are going to mention that there is a tool you should be
clear exactly who and what organization are behind it.

Thank you.