Re: linux capabilities ?

[Chris Wright <chrisw@osdl.org>]

* jnf (jnf@innocence-lost.us) wrote:
> I will read the paper before commenting on it further, however I cannot
> see what dangers it would really provide that a setuid program doesnt
> already have- other than the ability to give another non-root process root
> like abilities. However, the more I ponder it, it seems as if you could

It was a dangerous failure mode when a capability isn't present that hit
sendmail.

> accomplish a lot of things with a set of ACL's and Capabilities (think
> compartmentalizing everything from each other where no one thing has full
> control of anything other than its particular subsystem).

Yes, that's the ideal.  Unfortunately it doesn't work out quite so
neatly ;-/

> > Since /proc/kmsg is 0400 you need CAP_DAC_READ_SEARCH (don't necessarily
> > need full override).  Otherwise, you are right, you do need CAP_SYS_ADMIN.
> > Or just use syslog(2) directly, and you'll avoid the DAC requirement.
> 
> Hrm, even a chmod of it didn't appear to really affect things?

Should, and it makes a difference for me.

thanks,
-chris
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