Re: [PATCH] drivers: net: remove a dangling pointer in peak_usb_create_dev

[Pavel Skripkin <paskripkin@gmail.com>]

Hi Dongliang,

On 1/22/22 09:45, Dongliang Mu wrote:
[...]

>> Yeah, it seems like (at least based on code), that this dangling pointer
>> is not dangerous, since nothing accesses it. And next_siblings
>> _guaranteed_ to be NULL, since dev->next_siblings is set NULL in
>> disconnect()
> 
> Yes, you're right. As a security researcher, I am sensitive to such
> dangling pointers.
> 
> As its nullifying site is across functions, I suggest developers
> remove this dangling pointer in case that any newly added code in this
> function or before the nullifying location would touch next_siblings.
> 

Based on git blame this driver is very old (was added in 2012), so, I 
guess, nothing really new will come up.

Anyway, I am absolutely not a security person and if you think, that 
this dangling pointer can be somehow used in exploitation you should 
state it in commit message.


> If Pavel and others think it's fine, then it's time to close this patch.
> 

I don't have any big objections on the code itself. Maybe only 'if' can 
be removed to just speed up the code, but I don't see why this change is 
needed :)




With regards,
Pavel Skripkin