On Fri, 15.08.14 19:28, Stef Walter (st...@redhat.com) wrote: > > On 15.08.2014 18:56, Lennart Poettering wrote: > > On Fri, 15.08.14 18:25, Stef Walter (st...@redhat.com) wrote: > > > >> > >> On 13.08.2014 20:27, Lennart Poettering wrote: > >>> On Wed, 06.08.14 13:23, Stef Walter (st...@redhat.com) wrote: > >>> > >>>> I've done initial work on adding polkit support to systemd1 DBus > >>>> methods. You can see it here: > >> > >> Thanks for the review. Worked on this a bit more. > >> > >> I might drop off the face of the earth for a couple weeks. In case I do, > >> I thought I'd update my public branch. But if I'm around, I'll test and > >> prepare a patch set early next week. > >> > >>>> https://github.com/stefwalter/systemd/commits/polkit-systemd1 > > > > Hmm, yuck. There's a security issue here... Reading the capabilities > > from the sender on dbus1 is racy, since we have to read it from > > /proc/$PID/stat and don't get it sent along with the message, like we do > > on kdbus. A rogue client could send a message, quickly invoke some suid > > binary, and we'd consider the client trusted. > > > > Now for the low-level implementation of the vtable bit we are actually > > smart, and check by UID on dbus1, and by cap on kdbus, in order to avoid > > the vulnerability. > > > > Hmm, now I wonder how to best handle this for cases like this, we > > probably need some generic way how clients can make this decision in an > > always safe way... > > > > I need to think more about this... > > By the way, there's some similar problematic code in the modified > KillUnit() method implementation ... changed from specifying the > CAP_KILL in the vtable, and now it does a manual check. > > > Patch set looks great otherwise. I'll come up with something for the > > security issue, then adapt your patch, and merge it. > > I haven't tested the updated branch at all :) So it may go boom...
I have now pushed this, after reworking this on top some major changes to bus_verify_polkit(), which avoids having to pass the original callbacks through to the function that ultimately does the verification. While merging I also made another change, you are probably not going to like: I turned of the interactivity for the polkit checks. Interactivity needs to be optional, and it currently is for all out polkit-enabled bus methods. And we should do the same for the PID 1 offered methods. Now, of course, we should open this up for inetractive (after all, that's what polkit is good for), but we probably need a new set of methods for that, which take the original arguments but also take a boolean argument to enable ineractivity. Hence, we probably should have StartUnit2() in addition to StartUnit(). Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
