Home » Mailing lists » Devel » [patch 0/8] mount ownership and unprivileged mount syscall (v4)
Re: [patch 2/8] allow unprivileged umount [message #18453 is a reply to message #18427] |
Sun, 22 April 2007 06:47 ![Go to previous message Go to previous message](/theme/ovz3/images/up.png) ![Go to next message Go to previous message](/theme/ovz3/images/down.png) |
Miklos Szeredi
Messages: 161 Registered: April 2007
|
Senior Member |
|
|
> > On Sat, 21 Apr 2007 10:09:42 +0200 Miklos Szeredi <miklos@szeredi.hu> wrote:
> >
> >> > > +static bool permit_umount(struct vfsmount *mnt, int flags)
> >> > > +{
> >> > >
> >> > > ...
> >> > >
> >> > > + return mnt->mnt_uid == current->uid;
> >> > > +}
> >> >
> >> > Yes, this seems very wrong. I'd have thought that comparing user_struct*'s
> >> > would get us a heck of a lot closer to being able to support aliasing of
> >> > UIDs between different namespaces.
> >> >
> >>
> >> OK, I'll fix this up.
> >>
> >> Actually an earlier version of this patch did use user_struct's but
> >> I'd changed it to uids, because it's simpler.
> >
> > OK..
> >
> >> I didn't think about
> >> this being contrary to the id namespaces thing.
> >
> > Well I was madly assuming that when serarate UID namespaces are in use, UID
> > 42 in container A will have a different user_struct from UID 42 in
> > container B. I'd suggest that we provoke an opinion from Eric & co before
> > you do work on this.
>
> That is what I what I have been thinking as well,
Does this mean, that containers will need this? Or that you don't
know yet?
> storing a user struct on each mount point seems sane, plus it allows
> per user mount rlimits which is major plus. Especially since we
> seem to be doing accounting only for user mounts a per user rlimit
> seems good.
I'm not against per-user rlimits for mounts, but I'd rather do this
later...
> To get the user we should be user fs_uid as HPA suggested.
fsuid is exclusively used for checking file permissions, which we
don't do here anymore. So while it could be argued, that mount() _is_
a filesystem operation, it is really a different sort of filesystem
operation than the rest.
OTOH it wouldn't hurt to use fsuid instead of ruid...
> Finally I'm pretty certain the capability we should care about in
> this context is CAP_SETUID. Instead of CAP_SYS_ADMIN.
>
> If we have CAP_SETUID we can become which ever user owns the mount,
> and the root user in a container needs this, so he can run login
> programs. So changing the appropriate super user checks from
> CAP_SYS_ADMIN to CAP_SETUID I think is the right thing todo.
That's a flawed logic. If you want to mount as a specific user, and
you have CAP_SETUID, then just use set*uid() and then mount().
Changing the capability check for mount() would break the userspace
ABI.
Miklos
_______________________________________________
Containers mailing list
Containers@lists.linux-foundation.org
https://lists.linux-foundation.org/mailman/listinfo/containers
|
|
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 0/8] mount ownership and unprivileged mount syscall (v4)
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 1/8] add user mounts to the kernel
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
By: akpm on Sat, 21 April 2007 07:55
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
By: ebiederm on Sat, 21 April 2007 13:14
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
By: ebiederm on Sun, 22 April 2007 07:43
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 1/8] add user mounts to the kernel
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 2/8] allow unprivileged umount
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: akpm on Sat, 21 April 2007 07:55
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: hpa on Sat, 21 April 2007 08:01
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: akpm on Sat, 21 April 2007 08:36
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: ebiederm on Sat, 21 April 2007 12:53
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: ebiederm on Sat, 21 April 2007 13:29
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
By: ebiederm on Sun, 22 April 2007 07:09
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 2/8] allow unprivileged umount
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 3/8] account user mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 3/8] account user mounts
By: akpm on Sat, 21 April 2007 07:55
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 3/8] account user mounts
By: ebiederm on Sat, 21 April 2007 13:37
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 3/8] account user mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 3/8] account user mounts
By: ebiederm on Sun, 22 April 2007 07:49
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 3/8] account user mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 4/8] propagate error values from clone_mnt
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 4/8] propagate error values from clone_mnt
By: ebiederm on Sat, 21 April 2007 13:40
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 5/8] allow unprivileged bind mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 5/8] allow unprivileged bind mounts
By: ebiederm on Sat, 21 April 2007 14:00
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 5/8] allow unprivileged bind mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 6/8] put declaration of put_filesystem() in fs.h
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
By: akpm on Sat, 21 April 2007 07:55
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
By: ebiederm on Sat, 21 April 2007 14:10
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
By: ebiederm on Sat, 21 April 2007 16:57
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
By: ebiederm on Sat, 21 April 2007 21:00
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 7/8] allow unprivileged mounts
By: ebiederm on Sat, 21 April 2007 21:33
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
[patch 8/8] allow unprivileged fuse mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 8/8] allow unprivileged fuse mounts
By: akpm on Sat, 21 April 2007 07:55
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 8/8] allow unprivileged fuse mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 8/8] allow unprivileged fuse mounts
By: ebiederm on Sat, 21 April 2007 14:18
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 8/8] allow unprivileged fuse mounts
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 0/8] mount ownership and unprivileged mount syscall (v4)
By: ebiederm on Wed, 25 April 2007 01:04
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 0/8] mount ownership and unprivileged mount syscall (v4)
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 0/8] mount ownership and unprivileged mount syscall (v4)
|
![Read Message Read Message](/theme/ovz3/images/read.png) |
|
Re: [patch 0/8] mount ownership and unprivileged mount syscall (v4)
|
Goto Forum:
Current Time: Tue Jul 16 11:43:54 GMT 2024
Total time taken to generate the page: 0.02873 seconds
|