From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rui Xiang <rui.xiang-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCH 7/9] syslog_ns: implement function for creating syslog ns
Date: Tue, 30 Jul 2013 11:39:01 +0800
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To: Gu Zheng <guz.fnst-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
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List-Id: containers.vger.kernel.org

On 2013/7/29 18:25, Gu Zheng wrote:
> Hi Rui,
> 
> On 07/29/2013 10:31 AM, Rui Xiang wrote:
> 
>> Add create_syslog_ns function to create a new ns. We
>> must create a user_ns before create a new syslog ns.
>> And then tie the new syslog_ns to current user_ns
>> instead of original syslog_ns which comes from
>> parent user_ns.

...

>> diff --git a/kernel/printk.c b/kernel/printk.c
>> index fd2d600..6b561db 100644
>> --- a/kernel/printk.c
>> +++ b/kernel/printk.c
>> @@ -384,6 +384,10 @@ static int check_syslog_permissions(int type, bool from_file,
>>  		|| type == SYSLOG_ACTION_CONSOLE_LEVEL)
>>  		ns = &init_syslog_ns;
>>  
>> +	/* create a new syslog ns */
>> +	if (type == SYSLOG_ACTION_NEW_NS)
>> +		return 0;
>> +
> 
> Don't we need further permission or caps check here? Return success directly seems sloppy. 
> 
CAP_SYSLOG is checked in create_syslog_ns, so I think we can return 0 temporarily.