On 11/01/2013 09:21 AM, Steffen Klassert wrote:
> On some codepaths the skb does not have a dst entry
> when xfrm_decode_session() is called. So check for
> a valid skb_dst() before dereferencing the device
> interface index. We use 0 as the device index if
> there is no valid skb_dst(), or at reverse decoding
> we use skb_iif as device interface index.
> 
> Bug was introduced with git commit bafd4bd4dc
> ("xfrm: Decode sessions with output interface.").
> 
> Reported-by: Meelis Roos <mroos@linux.ee>
> Tested-by: Meelis Roos <mroos@linux.ee>
> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

Please queue this for 3.12-stable, I've seen this bug trigger a panic
when heavily using Bittorrent (screenshot:
http://i.imgur.com/OIKVccM.jpg )

Thanks,
Matthias