From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 2/2] tun: update file current position
Date: Fri, 06 Dec 2013 12:45:00 -0500 (EST)
Message-ID: <20131206.124500.1976272290413710707.davem@davemloft.net>
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	wuzhy@linux.vnet.ibm.com
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From: Zhi Yong Wu <zwu.kernel@gmail.com>
Date: Fri,  6 Dec 2013 17:08:50 +0800

> From: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
> 
> Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>

Also applied and queued up for -stable, thanks.

I noticed in these two cases that that min_t() adjustment of 'ret'
seems strange.  I can't understand why it's needed.

If, for example, tun_do_read() really did read more than 'len'
bytes:

1) That would write past the end of the buffer.

2) Writing a different value to the ->ki_pos would mean
   that ->ki_pos is now inaccurate.

Unless someone can explain why the min_t() is needed, we should remove
it.