Re: [patch] ADJ_OFFSET_SS_READ and capabilities

[Michael Kerrisk]

On Tue, Jul 1, 2008 at 12:07 AM, john stultz <johnstul@xxxxxxxxxx> wrote:
>
> On Sun, 2008-06-22 at 09:32 +0200, Michael Kerrisk wrote:
>> Hi Roman, John,
>>
>> ADJ_OFFSET_SS_READ is a read-only operation.  Therefore, it seems
>> reasonable not to require any capability (as is the case when 'modes'
>> is zero.  See the patch below.  Does this change seem reasonable?
>>
>> Cheers,
>>
>> Michael
>>
>> --- linux-2.6.26-rc5/kernel/time/ntp.c        2008-06-13 11:16:51.000000000 +0200
>> +++ linux-2.6.26-rc5-p/kernel/time/ntp.c      2008-06-22 07:31:43.000000000 +0200
>> @@ -281,7 +281,8 @@
>>       int result;
>>
>>       /* In order to modify anything, you gotta be super-user! */
>> -     if (txc->modes && !capable(CAP_SYS_TIME))
>> +     if (txc->modes && txc->modes != ADJ_OFFSET_SS_READ &&
>> +         !capable(CAP_SYS_TIME))
>>               return -EPERM;
>>
>>       /* Now we validate the data before disabling interrupts */
>>
>
>
> Hey Michael,
>        This seems like an ok change, but we'd first want to fix the issue you
> pointed out earlier which would make sure adjtimex() read calls don't
> cause side effects.

John, Roman,

Are you pushing this into 2.6.27-rc1?

Cheers,

Michael

-- 
Michael Kerrisk
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