From: Ian Kelling <ian@iankelling.org>
Date: Sun, 5 Feb 2017 04:05:45 +0000 (-0800)
Subject: change mount ns to slave
X-Git-Url: https://iankelling.org/git/?a=commitdiff_plain;h=b9cf4000a50a83b7f757212030e18b00104ab01f;p=newns

change mount ns to slave
---

diff --git a/newns b/newns
index 2896cf2..76c7adf 100755
--- a/newns
+++ b/newns
@@ -196,7 +196,17 @@ start() {
         touch /root/mount_namespaces/$nn
     fi
     if ! mountpoint /root/mount_namespaces/$nn >/dev/null; then
-        unshare --mount=/root/mount_namespaces/$nn
+        # documentation on propagation is a bit weird because it
+        # confusingly talks about binds, namespaces, and mirrors (which
+        # seems to be just another name for bind), shared subtrees
+        # (which seems to a term for binds and namespaces), and does not
+        # properly specify whether the documentation applies to binds,
+        # namespaces, or both. Notably, propagation for binds is marked
+        # on the original mount point, and propagation for a mount
+        # namespace is marked on mounts within the namespace.  Here, we
+        # specify that we want mount changes propagated to us, but not
+        # back.
+        unshare --propagation slave --mount=/root/mount_namespaces/$nn
     fi
     ####   end mount namespace setup ####