From mboxrd@z Thu Jan  1 00:00:00 1970
From: SF Markus Elfring <elfring@users.sourceforge.net>
Date: Fri, 05 Dec 2014 12:44:30 +0000
Subject: Re: [PATCH v2 5/6] net-PPP: Delete an unnecessary assignment in mppe_alloc()
Message-Id: <5481A8AE.9050506@users.sourceforge.net>
List-Id: <kernel-janitors.vger.kernel.org>
References: <530DD06F.4090703@users.sourceforge.net> <alpine.DEB.2.02.1402262129250.2221@localhost6.localdomain6> <5317A59D.4@users.sourceforge.net> <547B4886.4080406@users.sourceforge.net> <547B496E.604@users.sourceforge.net> <547C5CBC.6060607@cogentembedded.com> <547C82A6.2030808@users.sourceforge.net> <547CA157.1080401@cogentembedded.com> <5480DA32.8000201@users.sourceforge.net> <5480DDC1.6040101@users.sourceforge.net> <20141205122214.GB4912@mwanda>
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To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>, Paul Mackerras <paulus@samba.org>, linux-ppp@vger.kernel.org, netdev@vger.kernel.org, Eric Dumazet <eric.dumazet@gmail.com>, LKML <linux-kernel@vger.kernel.org>, kernel-janitors@vger.kernel.org, Julia Lawall <julia.lawall@lip6.fr>

>> The data structure element "arc4" was assigned a null pointer by the
>> mppe_alloc() function if a previous function call "crypto_alloc_blkcipher"
>> failed.
> 
> crypto_alloc_blkcipher() returns error pointers and not NULL.

That is true.


> This patch creates a bug.

Please explain: How?

Did you notice that the data structure element "arc4" was reset
to a null pointer if a failure was detected for the function
call "crypto_alloc_blkcipher"?

Do you find this specific assignment still necessary for exception
handling in the implementation of mppe_alloc() function?

Regards,
Markus