But if pam_console makes the locally logged-in user own /dev/rtc and be the only one 
able to read and write from it, doesn't your concern become moot?

Juan Quintela wrote:
>>>>>> "guillaume" == Guillaume Rousse <[EMAIL PROTECTED]> writes:
> 
> guillaume> Ainsi parlait Juan Quintela :
>>> >>>>> "olivier" == Olivier Blin <[EMAIL PROTECTED]> writes:
>>> >>
>>> >> # RTC resolution
>>> >> dev.rtc.max-user-freq = 1024
>>> >>
>>> >> Could this setting be added in default sysctl.conf ?
>>> 
> olivier> Thanks, but shouldn't this be the default in default security
>>> level ? olivier> RTC works fine, but sysctl.conf need to be tweaked.
> olivier> IMHO, the user shouldn't have to do that.
>>> 
>>> Problem is that in a multiuser system, if you allow the value 1024,
>>> you can create a DOS if several users use that.
> guillaume> I guess most multimedia applications are only usable by local user, not a 
> guillaume> remote one, which means only one at a time. This should reduce DOS risks, 
> no?
> 
> No.  any user can do a very small script/c program an use the whole
> number of timers.  Machine is on its knees :(
> 
> guillaume> What about adding this setting only through mplayer, tvtime
> guillaume> and other packages requiring it %post/%postun facilities ?
> 
> Really it is too agresive to set it _unconditionally_.
> 
> 
>>> Default value of 64 should be enough except for single-user machines
>>> running an _almost_ real time application.  And yes, for today
>>> machines, mplayer is still real-time like application.
> guillaume> Not sure to understand what you mean there.
> 
> That the value only make sense for single user machines, or for
> machines when you trust all the users will not do something
> dumb/trying to crash your server.
> 
> Only way to handle it automagically is having a option in the
> installer/MCC telling something like:
> 
> - this is a mono-user system/I trust all the users
> 
> Only other easy thing that I can think is teaching msec to set it at
> the most "unsecure" level.  And I am not sure that people will be
> using that level at all :(
> 
> Later, Juan.
> 



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