From mboxrd@z Thu Jan  1 00:00:00 1970
From: Brian Haley <brian.haley@hp.com>
Subject: Re: [PATCH net-next] sockopt: Make SO_BINDTODEVICE readable
Date: Tue, 23 Oct 2012 17:43:23 -0400
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Cc: Pavel Emelyanov <xemul@parallels.com>,
	Linux Netdev List <netdev@vger.kernel.org>,
	David Miller <davem@davemloft.net>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 10/22/2012 05:52 PM, Eric Dumazet wrote:

>>> I meant another cpu can be changing dev->name[] content while the
>>> strcpy() is done, and you get a mangled devname, like "for" or "bao"
>>> instead of "foo" or "bar"
>>
>> Even when holding the rcu_read_lock()?  I'd have to hold the rtnl lock there?
> 
> Yes, rcu_read_lock() only makes sure the device doesnt disappear.
> 
> But its name can be changed.

There's a similar bug in the SIOCGIFNAME/dev_ifname() code too then, but I would
think this rare enough that it doesn't happen in practice.

-Brian