Subject: Re: [PATCH] tun: don't zeroize sock->file on detach

From: Stanislav Kinsbursky <[email-masked]>
Date: Tue, 21 Aug 2012 20:04:41 +0400

10.08.2012 03:16, David Miller пишет:
> From: Stanislav Kinsbursky <[email-masked]>
> 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 leads to
>> oops for non-persistent devices:
>>
>> tun_chr_close()
>> tun_detach()				<== tun->socket.file = NULL
>> tun_free_netdev()
>> sk_release_sock()
>> sock_release(sock->file == NULL)
>> iput(SOCK_INODE(sock))			<== dereference on NULL pointer
>>
>> This patch just removes zeroing of socket's file from __tun_detach().
>> sock_release() will do this.
>>
>> Cc: [email-masked]
>> Reported-by: Ruan Zhijie <[email-masked]>
>> Tested-by: Ruan Zhijie <[email-masked]>
>> Acked-by: Al Viro <[email-masked]>
>> Acked-by: Eric Dumazet <[email-masked]>
>> Acked-by: Yuchung Cheng <[email-masked]>
>> Signed-off-by: Stanislav Kinsbursky <[email-masked]>
>
> 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.

-- 
Best regards,
Stanislav Kinsbursky