Re: [RFC] Let non-root users eject their ipods?

From: Sander
Date: Tue Dec 20 2005 - 04:37:38 EST


Coywolf Qi Hunt wrote (ao):
> 2005/12/20, Sander <sander@xxxxxxxxxxx>:
> > Coywolf Qi Hunt wrote (ao):
> > > 2005/12/20, Willy Tarreau <willy@xxxxxxxxx>:
> > > > On Mon, Dec 19, 2005 at 06:51:58PM -0800, john stultz wrote:
> > > > > I'm getting a little tired of my roommates not knowing how to safely
> > > > > eject their usb-flash disks from my system and I'd personally like it if
> > > > > I could avoid bringing up a root shell to eject my ipod. Sure, one could
> > > > > suid the eject command, but that seems just as bad as changing the
> > > > > permissions in the kernel (eject wouldn't be able to check if the user
> > > > > has read/write permissions on the device, allowing them to eject
> > > > > anything).
> > > >
> > > > You may find my question stupid, but what is wrong with umount ? That's
> > > > how I proceed with usb-flash and I've never sent any eject command to
> > > > it (I even didn't know that the ioctl would be accepted by an sd device).
> > >
> > > IMHO, umount doesn't guarantee sync, isn't it?
>
> Actually I was think umount(2), since this is the kernel list, but off
> topic here.
>
> >
> > I'm pretty sure it does :-)
>
> That is because: usually your removable media is not the file system
> root, hence umount(8) can return successfully only if no processes are
> busy working on it.
>
> If you boot from or chroot/pivot into a removable media, and you
> remount it ro, and unplug it, then you may lose data.

eject wont help you here, right?

And the OP was talking about usb-flash sticks his roommates use and his
ipod. He doesn't need to eject those. umount will do.

--
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http://www.humilis.net
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