Seth Arnold wrote: > On Fri, Dec 08, 2006 at 01:36:57PM -0600, Serge E. Hallyn wrote: > >> The other is that root can lose capabilities by executing files with >> only some capabilities set. The next two patches change these >> behaviors. >> > I saw this in my code review and thought that this behaviour was > intentional. :) It seemed like a good idea to me.. > It really depends on which threat you are trying to defend against.
Serge is correct that it does not prevent root from copying the file, messing with the attributes, and running it anyway. However, I don't see file capabilities as being intended to try to confine root. Rather, it seems like it is intended to make it easier to manage what capabilities should usually be present when the program is run. E.g. the file has a limited capability set so that root can run it and not have to think about overtly dropping privs or su'ing to a non-privileged user to be able to run it safely. So I'm with Seth; it sounds like a feature, not a bug. Caveat: I have no clue what the POSIX.1e committee intended. But since none of the POSIX-alike implementations are compatible with each other anyway, I don't really care :) Crispin -- Crispin Cowan, Ph.D. http://crispincowan.com/~crispin/ Director of Software Engineering, Novell http://novell.com Hacking is exploiting the gap between "intent" and "implementation" - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/