Re: [PATCH] kernel/groups.c: consider about NULL for 'group_info' in all related extern functions

Chen Gang
2013-09-25T00:50:39Z

On 09/24/2013 08:04 PM, Tejun Heo wrote:
> On Tue, Sep 24, 2013 at 12:27:36PM +0800, Chen Gang wrote:
>> For real world, /sbin/init will call setgroups, so user space 'help'
>> kernel itself to protect this issue, but I think, we don't only depend
>> on the user space help checking.
>>
>> The proof is below:
>>
>> [root@gchenlinux tmp]# grep setgroups /sbin/*
>> Binary file /sbin/init matches
>> Binary file /sbin/rpc.statd matches
>> Binary file /sbin/rsyslogd matches
>> Binary file /sbin/runuser matches
>>
>> From reading kernel source code, kernel itself does not intend to set
>> 'group_info', it is triggered by user space or another kernel mode
>> sub-systems.
>
> Can you please demonstrate such failure? You can tell kernel to
> execute a given binary instead of init with "init=" param.
>

OK, I will/should try, today (although I have to spend my additional
time resource on it. :-( ).

Hmm... in fact, in my opinion, interface (especially content system
call) need make itself consistency, although at present, it can not
cause issue.

> Thanks.
>

Thanks.
--
Chen Gang