From: Miklos Szeredi <mszeredi@suse.cz>

There's a missing check for CAP_SYS_ADMIN in do_change_type().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/namespace.c |    3 +++
 1 file changed, 3 insertions(+)

diff -puN fs/namespace.c~check-privileges-before-setting-mount-propagation fs/namespace.c
--- a/fs/namespace.c~check-privileges-before-setting-mount-propagation
+++ a/fs/namespace.c
@@ -886,6 +886,9 @@ static int do_change_type(struct nameida
 	int recurse = flag & MS_REC;
 	int type = flag & ~MS_REC;
 
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
 	if (nd->dentry != nd->mnt->mnt_root)
 		return -EINVAL;
 
_