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Message-ID: <5481A8AE.9050506@users.sourceforge.net>
Date: Fri, 05 Dec 2014 13:44:30 +0100
From: SF Markus Elfring <elfring@users.sourceforge.net>
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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>
Subject: Re: [PATCH v2 5/6] net-PPP: Delete an unnecessary assignment in mppe_alloc()
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>> 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