From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stanislav Kinsbursky <skinsbursky@parallels.com>
Subject: Re: [PATCH] tun: don't zeroize sock->file on detach
Date: Tue, 21 Aug 2012 20:04:41 +0400
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To: David Miller <davem@davemloft.net>
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10.08.2012 03:16, David Miller =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> From: Stanislav Kinsbursky <skinsbursky@parallels.com>
> Date: Thu, 09 Aug 2012 16:50:40 +0400
>
>> This is a fix for bug, introduced in 3.4 kernel by commit
>> 1ab5ecb90cb6a3df1476e052f76a6e8f6511cb3d, which, among other things,=
 replaced
>> simple sock_put() by sk_release_kernel(). Below is sequence, which l=
eads to
>> oops for non-persistent devices:
>>
>> tun_chr_close()
>> tun_detach()				<=3D=3D tun->socket.file =3D NULL
>> tun_free_netdev()
>> sk_release_sock()
>> sock_release(sock->file =3D=3D NULL)
>> iput(SOCK_INODE(sock))			<=3D=3D dereference on NULL pointer
>>
>> This patch just removes zeroing of socket's file from __tun_detach()=
=2E
>> sock_release() will do this.
>>
>> Cc: stable@vger.kernel.org
>> Reported-by: Ruan Zhijie <ruanzhijie@hotmail.com>
>> Tested-by: Ruan Zhijie <ruanzhijie@hotmail.com>
>> Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
>> Acked-by: Eric Dumazet <edumazet@google.com>
>> Acked-by: Yuchung Cheng <ycheng@google.com>
>> Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
>
> Applied, thanks.
>

Hi, David.
I found out, that this commit: b09e786bd1dd66418b69348cb110f3a64764626a
was previous attempt to fix the problem.
I believe this commit have to be dropped.


--=20
Best regards,
Stanislav Kinsbursky