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From: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com>
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
Subject: Re: jsm_tty: Fix a possible null pointer dereference in two functions
Date: Wed, 6 Dec 2017 14:16:21 -0200	[thread overview]
Message-ID: <8ae240fa-7f77-8f4c-225c-853cdda73a67@linux.vnet.ibm.com> (raw)
In-Reply-To: <089a4b85-64e8-cb4a-c5f8-9abb2556e5e5@users.sourceforge.net>



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


  parent reply	other threads:[~2017-12-06 16:16 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-11-29 16:40 [PATCH] jsm_tty: Fix a possible null pointer dereference in two functions SF Markus Elfring
2017-11-29 17:23 ` Joe Perches
2017-11-29 17:35   ` Greg Kroah-Hartman
2017-11-29 17:51     ` Joe Perches
2017-11-29 18:05       ` Greg Kroah-Hartman
2017-11-29 18:16         ` Joe Perches
2017-11-29 18:19         ` SF Markus Elfring
2017-11-30  6:41           ` Jiri Slaby
2017-12-06 16:16           ` Guilherme G. Piccoli [this message]
2017-12-16  6:27             ` jsm_tty: Deletion of a null pointer check in two functions? SF Markus Elfring
2017-12-18 14:36               ` Guilherme G. Piccoli
2017-12-18 17:14                 ` SF Markus Elfring
2017-11-29 19:16   ` [PATCH] jsm_tty: Fix a possible null pointer dereference in two functions Dan Carpenter

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