diff --git a/fs/namespace.c b/fs/namespace.c
index a3035223d4218c13ac6db83f8d5444e454346c2f..8505b5ece5de98bc41a9a00efcb0a11035607508 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1713,6 +1713,9 @@ static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
 	if (readonly_request == __mnt_is_readonly(mnt))
 		return 0;
 
+	if (mnt->mnt_flags & MNT_LOCK_READONLY)
+		return -EPERM;
+
 	if (readonly_request)
 		error = mnt_make_readonly(real_mount(mnt));
 	else
diff --git a/include/linux/mount.h b/include/linux/mount.h
index d7029f4a191a093ef9294104c75756b6d3b7faee..73005f9957ead2b95adb4107329434afbbf482a7 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -47,6 +47,8 @@ struct mnt_namespace;
 
 #define MNT_INTERNAL	0x4000
 
+#define MNT_LOCK_READONLY	0x400000
+
 struct vfsmount {
 	struct dentry *mnt_root;	/* root of the mounted tree */
 	struct super_block *mnt_sb;	/* pointer to superblock */