Re: Mount namespace "dominant peer group"?
From: Michael Kerrisk (man-pages)
Date: Tue May 24 2016 - 18:58:12 EST
On 05/23/2016 02:55 AM, Miklos Szeredi wrote:
> C is slave of B is slave of A. If a process can see (i.e. has under
> its root) A and C but not B then for C it will show
> master:B,propagate_from:A. This piece of information is shown because
> it can't see the immediate master (B) and so cannot determine the
> chain of propagation between the mounts it can see.
> Concrete example:
Yep, that does it. Thanks for the walk through!
One piece missing below though, in case anyone else tries to walk
> # mount --bind / /mnt
> # mount --bind /proc /mnt/proc
> # mount --make-private /mnt
> # mount --make-shared /mnt
> # mkdir /tmp/etc
> # mount --bind /mnt/etc /tmp/etc
> # mount --make-slave /tmp/etc
> # mount --make-shared /tmp/etc
# mkdir /mnt/tmp/etc
> # mount --bind /tmp/etc /mnt/tmp/etc
> # mount --make-slave /mnt/tmp/etc
> # cat /proc/self/mountinfo | grep /tmp/etc
> 164 40 253:1 /etc /tmp/etc rw,relatime shared:100 master:97 - ...
> # chroot /mnt
> # cat /proc/self/mountinfo
> 129 62 253:1 / / rw,relatime shared:97 - ...
> 168 129 253:1 /etc /tmp/etc rw,relatime master:100 propagate_from:97 - ...
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