Re: [PATCH v2 1/3] net: hold sock reference while processing tx timestamps

[David Miller <davem@davemloft.net>]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 21 Oct 2011 13:31:50 +0200

> Le vendredi 21 octobre 2011 à 12:49 +0200, Richard Cochran a écrit :
>> The pair of functions,
>> 
>>  * skb_clone_tx_timestamp()
>>  * skb_complete_tx_timestamp()
>> 
>> were designed to allow timestamping in PHY devices. The first
>> function, called during the MAC driver's hard_xmit method, identifies
>> PTP protocol packets, clones them, and gives them to the PHY device
>> driver. The PHY driver may hold onto the packet and deliver it at a
>> later time using the second function, which adds the packet to the
>> socket's error queue.
>> 
>> As pointed out by Johannes, nothing prevents the socket from
>> disappearing while the cloned packet is sitting in the PHY driver
>> awaiting a timestamp. This patch fixes the issue by taking a reference
>> on the socket for each such packet. In addition, the comments
>> regarding the usage of these function are expanded to highlight the
>> rule that PHY drivers must use skb_complete_tx_timestamp() to release
>> the packet, in order to release the socket reference, too.
>> 
>> These functions first appeared in v2.6.36.
>> 
>> Reported-by: Johannes Berg <johannes@sipsolutions.net>
>> Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
>> Cc: <stable@vger.kernel.org>
>> ---
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied.