Re: [PATCH 3/4] autofs - make mountpoint checks namespace aware

[Omar Sandoval <osandov@osandov.com>]

On Wed, Sep 14, 2016 at 02:14:45PM +0800, Ian Kent wrote:
> If an automount mount is clone(2)ed into a file system that is
> propagation private, when it later expires in the originating
> namespace subsequent calls to autofs ->d_automount() for that
> dentry in the original namespace will return ELOOP until the
> mount is manually umounted in the cloned namespace.
> 
> In the same way, if an autofs mount is triggered by automount(8)
> running within a container the dentry will be seen as mounted in
> the root init namespace and calls to ->d_automount() in that namespace
> will return ELOOP until the mount is umounted within the container.
> 
> Also, have_submounts() can return an incorect result when a mount
> exists in a namespace other than the one being checked.
> 
> Signed-off-by: Ian Kent <raven@themaw.net>
> Cc: Al Viro <viro@ZenIV.linux.org.uk>
> Cc: Eric W. Biederman <ebiederm@xmission.com>
> Cc: Omar Sandoval <osandov@osandov.com>

I can confirm that this fixes my repro and hasn't caused any other
problems as far as I can tell.

Tested-by: Omar Sandoval <osandov@fb.com>

-- 
Omar