From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [net] ixgbe: fix crash in build_skb Rx code path
Date: Mon, 26 Feb 2018 13:47:49 -0500 (EST)
Message-ID: <20180226.134749.1372103055616948220.davem@davemloft.net>
References: <20180223203941.3193-1-jeffrey.t.kirsher@intel.com>
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Cc: emil.s.tantilov@intel.com, netdev@vger.kernel.org,
        nhorman@redhat.com, sassmann@redhat.com, jogreene@redhat.com,
        stable@vger.kernel.org
To: jeffrey.t.kirsher@intel.com
Return-path: <stable-owner@vger.kernel.org>
In-Reply-To: <20180223203941.3193-1-jeffrey.t.kirsher@intel.com>
Sender: stable-owner@vger.kernel.org
List-Id: netdev.vger.kernel.org

From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Fri, 23 Feb 2018 12:39:41 -0800

> From: Emil Tantilov <emil.s.tantilov@intel.com>
> 
> Add check for build_skb enabled ring in ixgbe_dma_sync_frag().
> In that case &skb_shinfo(skb)->frags[0] may not always be set which
> can lead to a crash. Instead we derive the page offset from skb->data.
> 
> Fixes: 42073d91a214
> ("ixgbe: Have the CPU take ownership of the buffers sooner")
> CC: stable <stable@vger.kernel.org>
> Reported-by: Ambarish Soman <asoman@redhat.com>
> Suggested-by: Alexander Duyck <alexander.h.duyck@intel.com>
> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
> Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

Applied, thanks Jeff.