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Date: Sat, 20 Aug 2016 19:12:33 -0700 (PDT)
Message-Id: <20160820.191233.1040358497240261402.davem@davemloft.net>
To: christophe.jaillet@wanadoo.fr
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Subject: Re: [PATCH] wan-cosa: Use memdup_user() rather than duplicating
 its implementation
From: David Miller <davem@davemloft.net>
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From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Sat, 20 Aug 2016 10:42:54 +0200

> Le 20/08/2016 à 10:25, SF Markus Elfring a écrit :
>> @@ -875,16 +875,10 @@ static ssize_t cosa_write(struct file *file,
>>   	if (count > COSA_MTU)
>>   		count = COSA_MTU;
>>   	
>> -	/* Allocate the buffer */
>> -	kbuf = kmalloc(count, GFP_KERNEL|GFP_DMA);
> In this case, 'memdup_user()' has a different meaning, as GFP_DMA will
> no more be used for this memory allocation.

Agreed, this transformation is not equivalent.

Markus, please do not make these changes so blindly.