Messages in this thread | | | Date | Fri, 30 Mar 2012 18:40:35 +0400 | From | Cyrill Gorcunov <> | Subject | Re: [rfc] fcntl: Add F_GETOWNER_UIDS option |
| |
On Fri, Mar 30, 2012 at 09:12:19AM -0500, Serge Hallyn wrote: ... > > > > Yes, I wanna take a look on Eric's set first just to get right > > "picture" of everything. And I wanted to find a minimal solution > > with current kernel code base which could be extended in future. > > > > That said I guess the current init-ns-only approach should do the > > trick for a while. And (thanks for pointing) I need to add a test > > if a caller which tries to obtain uids has enought credentials > > for that (probably CAP_FOWNER), right? > > Sorry, I'm not sure which caller you mean. Neither f_setown nor > f_getown require privilege right now. Oh, you mean at restart?
I meant the dumper. Yes, at moment f_get/setown requires no privileges but I'm not sure if uid/euid is same or less sensible information than pid, that's why I though CAP_FOWNER might be worth to add, no?
> f_setown to someone else's uid/pid means you may cause a signal to > be sent to them. So CAP_KILL might be good? You do through that > signal get *some* info about the file writes, though not contents. > So yeah, maybe (CAP_KILL|CAP_FOWNER). ... > > I suspect operating with kuid's will be a way more easier. > > Yeah, I keep going back and forth on which makes more sense. But > kuid's probably make more sense, even though they aren't what > userspace in container will see. When you restore, the mapping > will give userspace what it expects; and if you're going to > restart in a container with a different mapping, then you'll > have to convert the filesystem as well since its inodes will > store kuids, so may as well also convert the kuids in the > checkpoint image then.
Agreed (if only I'm not missimg somethig ;)
Cyrill
| |