Re: [PATCH 24/32] vfs: syscall: Add fsopen() to prepare for superblock creation [ver #9]

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

 



Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:

> > Also you can't currently directly create a bind mount from userspace as you
> > can only bind from another path point - which you may not be able to access
> > (either by permission failure or because it's not in your mount namespace).
> > 
> 
> Are you trying to preserve the magic bind semantics with the new API?

No, I'm pointing out that you can't emulate this by doing a bind mount from
userspace if you can't access the thing you're binding from.

Now, we could create a syscall that just picks up an extant superblock using a
device and attaches it to a mount for you, but that would have to be at least
partially parameterised - which would be very fs-dependent - so that it can
know whether or not you're allowed to create another mount to that sb.

What you're talking about is emulating sget() in userspace - when we have to
do it in the kernel anyway if we still offer mount(2).

David



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux