From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
Subject: Re: jsm_tty: Fix a possible null pointer dereference in two functions
Date: Wed, 6 Dec 2017 14:16:21 -0200
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To: SF Markus Elfring <elfring@users.sourceforge.net>, linux-serial@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Joe Perches <joe@perches.com>, Jiri Slaby <jslaby@suse.com>, LKML <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org
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On 11/29/2017 04:19 PM, SF Markus Elfring wrote:
>>> It's pretty unlikely, but it is an actual defect.
>>
>> No it is not, those variables will never be set to NULL,
>> so this can never be triggered.  Walk up the call chain.
> 
> If the involved software developers are convinced about the validity
> of this pointer:
> 
> How do you think about to delete the following condition check
> instead in the discussed function implementations?
> 
> 	if (!ch)
> 		return;
> 
> 
> Regards,
> Markus
> 

Thanks for the fix.
I was on vacation - but now seeing all the analysis made here, if "ch"
can't be NULL then please go ahead and remove the check =)
I observed that this check comes from before Git, so really ancient code...

Cheers,


Guilherme