'attached' serves as a proxy for "source is a subtree of our namespace
and not the entirety of anon namespace"; finish massaging it away.
Reviewed-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
fs/namespace.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index 912c64d1dd79..b6f2172aa5e1 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3600,7 +3600,7 @@ static int do_move_mount(struct path *old_path,
struct mount *parent;
struct mountpoint *mp;
int err;
- bool attached, beneath = flags & MNT_TREE_BENEATH;
+ bool beneath = flags & MNT_TREE_BENEATH;
mp = do_lock_mount(new_path, beneath);
if (IS_ERR(mp))
@@ -3609,7 +3609,6 @@ static int do_move_mount(struct path *old_path,
old = real_mount(old_path->mnt);
p = real_mount(new_path->mnt);
parent = old->mnt_parent;
- attached = mnt_has_parent(old);
ns = old->mnt_ns;
err = -EINVAL;
@@ -3622,6 +3621,9 @@ static int do_move_mount(struct path *old_path,
/* ... and the target should be in our namespace */
if (!check_mnt(p))
goto out;
+ /* parent of the source should not be shared */
+ if (IS_MNT_SHARED(parent))
+ goto out;
} else {
/*
* otherwise the source must be the root of some anon namespace.
@@ -3649,11 +3651,6 @@ static int do_move_mount(struct path *old_path,
if (d_is_dir(new_path->dentry) !=
d_is_dir(old_path->dentry))
goto out;
- /*
- * Don't move a mount residing in a shared parent.
- */
- if (attached && IS_MNT_SHARED(parent))
- goto out;
if (beneath) {
err = can_move_mount_beneath(old_path, new_path, mp);
@@ -3686,7 +3683,7 @@ static int do_move_mount(struct path *old_path,
out:
unlock_mount(mp);
if (!err) {
- if (attached) {
+ if (!is_anon_ns(ns)) {
mntput_no_expire(parent);
} else {
/* Make sure we notice when we leak mounts. */
--
2.39.5
