From mboxrd@z Thu Jan  1 00:00:00 1970
From: Xiaotian Feng <dfeng@redhat.com>
Subject: Re: [PATCH] net dst: fix percpu_counter list corruption and poison
 overwritten
Date: Wed, 03 Nov 2010 13:25:03 +0800
Message-ID: <4CD0F22F.9000503@redhat.com>
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	"David S. Miller" <davem@davemloft.net>,
	Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
	"Pekka Savola (ipv6)" <pekkas@netcore.fi>,
	James Morris <jmorris@namei.org>,
	Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
	Patrick McHardy <kaber@trash.net>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On 11/03/2010 01:22 PM, Eric Dumazet wrote:
> Le mercredi 03 novembre 2010 =C3=A0 10:11 +0800, Xiaotian Feng a =C3=A9=
crit :
>> There're some percpu_counter list corruption and poison overwritten =
warnings
>> in recent kernel, which is resulted by fc66f95c.
>>
>> commit fc66f95c switches to use percpu_counter, in ip6_route_net_ini=
t, kernel
>> init the percpu_counter for dst entries, but, the percpu_counter is =
never destroyed
>> in ip6_route_net_exit. So if the related data is freed by kernel, th=
e freed percpu_counter
>> is still on the list, then if we insert/remove other percpu_counter,=
 list corruption
>> resulted. Also, if the insert/remove option modifies the ->prev,->ne=
xt pointer of
>> the freed value, the poison overwritten is resulted then.
>>
>> With the following patch, the percpu_counter list corruption and poi=
son overwritten
>> warnings disappeared.
>>
>> Signed-off-by: Xiaotian Feng<dfeng@redhat.com>
>> Cc: "David S. Miller"<davem@davemloft.net>
>> Cc: Alexey Kuznetsov<kuznet@ms2.inr.ac.ru>
>> Cc: "Pekka Savola (ipv6)"<pekkas@netcore.fi>
>> Cc: James Morris<jmorris@namei.org>
>> Cc: Hideaki YOSHIFUJI<yoshfuji@linux-ipv6.org>
>> Cc: Patrick McHardy<kaber@trash.net>
>> ---
>
> Good catch, thanks !
>
> Any reason you didnt Cc me (the author of the patch) ?
Sorry, I just used get_maintainer.pl to get the cc list...
>
> Acked-by: Eric Dumazet<eric.dumazet@gmail.com>
>
>
>
>