David Wagner wrote: > James Morris wrote: > >> [...] you can change the behavior of the application and then bypass >> policy entirely by utilizing any mechanism other than direct filesystem >> access: IPC, shared memory, Unix domain sockets, local IP networking, >> remote networking etc. >> > [...] > >> Just look at their code and their own description of AppArmor. >> > My gosh, you're right. What the heck? With all due respect to the > developers of AppArmor, I can't help thinking that that's pretty lame. > I think this raises substantial questions about the value of AppArmor. > What is the point of having a jail if it leaves gaping holes that > malicious code could use to escape? > > And why isn't this documented clearly, with the implications fully > explained? > > I would like to hear the AppArmor developers defend this design decision. > It was a simplicity trade off at the time, when AppArmor was mostly aimed at servers, and there was no HAL or DBUS. Now it is definitely a limitation that we are addressing. We are working on a mediation system for what kind of IPC a confined process can do http://forge.novell.com/pipermail/apparmor-dev/2007-April/000503.html
When our IPC mediation system is code instead of vapor, it will also appear here for review. Meanwhile, AppArmor does not make IPC security any worse, confined processes are still subject to the usual Linux IPC restrictions. AppArmor actually makes the IPC situation somewhat more secure than stock Linux, e.g. normal DBUS deployment can be controlled through file access permissions. But we are not claiming AppArmor to be an IPC security enhancement, yet. The proposed set of patches is a self-contained access control system for file system access, and we would like it reviewed as such. Current AppArmor docs are quite explicit that AppArmor only mediates file access and POSIX.1e capabilities. Crispin -- Crispin Cowan, Ph.D. http://crispincowan.com/~crispin/ Director of Software Engineering http://novell.com - 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/
