From mboxrd@z Thu Jan  1 00:00:00 1970
From: Romain Francoise <romain@orebokech.com>
Subject: Re: [PATCH] xfrm: fix xfrm_input/xfrm_tunnel_check oops
Date: Tue, 07 Apr 2015 14:14:43 +0200
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References: <20150402075824.GA2079@p183.telecom.by>
	<20150407085731.GH20559@secunet.com>
	<20150407114341.GA4492@p183.telecom.by>
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Cc: Steffen Klassert <steffen.klassert@secunet.com>,
	davem@davemloft.net, mike@normi.net, netdev@vger.kernel.org,
	herbert@gondor.apana.org.au
To: Alexey Dobriyan <adobriyan@gmail.com>
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In-Reply-To: <20150407114341.GA4492@p183.telecom.by> (Alexey Dobriyan's
	message of "Tue, 7 Apr 2015 14:43:41 +0300")
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On Tue, Apr 07, 2015 at 02:43:41PM +0300, Alexey Dobriyan wrote:
> On Tue, Apr 07, 2015 at 10:57:32AM +0200, Steffen Klassert wrote:
>> On Thu, Apr 02, 2015 at 10:58:24AM +0300, Alexey Dobriyan wrote:
>> > https://bugzilla.kernel.org/show_bug.cgi?id=95211
>> > 
>> > Commit 70be6c91c86596ad2b60c73587880b47df170a41
>> > ("xfrm: Add xfrm_tunnel_skb_cb to the skb common buffer") added check
>> > which dereferences ->outer_mode too early but larval SAs don't have
>> > this pointer set (yet). So check for tunnel stuff later.
>> > 
>> > Mike Noordermeer reported this bug and patiently applied all the debugging.
>> > 
>> > Technically this is remote-oops-in-interrupt-context type of thing.
>> > 
>> > BUG: unable to handle kernel NULL pointer dereference at 0000000000000034
>> > IP: [<ffffffff8150dca2>] xfrm_input+0x3c2/0x5a0
>> > 	...
>> > [<ffffffff81500fc6>] ? xfrm4_esp_rcv+0x36/0x70
>> > [<ffffffff814acc9a>] ? ip_local_deliver_finish+0x9a/0x200
>> > [<ffffffff81471b83>] ? __netif_receive_skb_core+0x6f3/0x8f0
>> > 	...
>> > 
>> > RIP  [<ffffffff8150dca2>] xfrm_input+0x3c2/0x5a0
>> > Kernel panic - not syncing: Fatal exception in interrupt
>> > 
>> > Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
>> 
>> Good catch!
>> 
>> Applied to the ipsec tree, thanks everyone!

> For the record Mike confirmed that the patch works:
> https://bugzilla.kernel.org/show_bug.cgi?id=95211#c20

Does this only affect configurations that use VTI? It's not clear from
the description.

Thanks.