From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Subject: Re: [PATCH v2] arc_emac: fix potential use after free
Date: Fri, 20 Dec 2013 14:06:07 +0000
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On Thu, 2013-12-19 at 18:10 -0800, Eric Dumazet wrote:
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> 
> skb_tx_timestamp(skb) should be called _before_ TX completion
> has a chance to trigger, otherwise it is too late and we access
> freed memory.
> 
> Fixes: e4f2379db6c6 ("ethernet/arc/arc_emac - Add new driver")

Hi Eric,

thanks for this fix.

Indeed I missed this part and description of "skb_tx_timestamp" which
clearly directs to use it earlier:
=======
 * skb_tx_timestamp() - Driver hook for transmit timestamping
 *
 * Ethernet MAC Drivers should call this function in their hard_xmit()
 * function immediately before giving the sk_buff to the MAC hardware.
=======

-Alexey