[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#342455: tech-ctte: Ownership and permissions of device mapper block devices



On Sat, Dec 17, 2005 at 03:09:37PM +0000, Roger Leigh wrote:
> Bastian Blank <waldi@debian.org> writes:
> 
> > On Sat, Dec 17, 2005 at 12:41:17PM +0000, Roger Leigh wrote:
> >> > Which procedure? You seem to know something I don't know. ("Overwrite"
> >> > means in my context: chmod of static devices or a MODE setting in the
> >> > udev config)
> >> A chown/chmod of the device is not scalable or practical.
> >
> > You recreate the complete /dev?
> 
> lvcreate/vgchange and related commands will create the devices with
> the default ownership, and hence require *manual* correction after
> their creation.  Thus chown/chmod are not practical for anything but
> tiny and unchanging installations.

Hu? lvcreate don't create static devices.

> 
> >> a new LV, the permissions will be wrong.  If I run vgchange, the
> >> permissions will be wrong.  This is not a solution.
> >
> > And I don't speak about libdevmapper managed device.
> 
> Please could you clarify?  What *are* you speaking about.  I'm
> referring to the fact that when I create or change an LVM LV, I have
> to manually correct the permissions (on both static and udev managed
> systems).

Lets quote myself:
|  means in my context: chmod of static devices or a MODE setting in the
| udev config)

This does not qualify dm devices.

> > SUBSYSTEM=="block", MODE="0600"
> 
> That changes the default permissions for block devices, but this is
> not what I meant.
> 
> How do I get device-mapper devices to be created by udev, along with
> the related symlinks?  The rule you suggest above does not in any way
> affect the *device-mapper* device permissions or ownership, which is
> the problem at hand:

KERNEL=="dm-[0-9]*", ACTION=="add", PROGRAM="/sbin/dmsetup info -c --noopencount --noheadings -o name -j %M -m %m", SYMLINK="disk/by-name/%c"

as shipped by suse.

> Also, you have not addressed the case where udev is not in use: the
> ownership and permissions are still wrong.

The settings are a secure default.

Anyway, what are the problems with a default of 666? It fixes any of the
problems.

Bastian

-- 
The heart is not a logical organ.
		-- Dr. Janet Wallace, "The Deadly Years", stardate 3479.4



Reply to: