On Wed, Aug 14, 2013 at 9:32 PM, Eric W. Biederman <ebiederm@xxxxxxxxxxxx> wrote: >> The solution is also theoretically simple: mounts in unpriv namespaces >> are marked "volatile" and are dissolved on an unlink type operation. >> >> Such volatile mounts would be useful in general too. > > Agreed. > > This is a problem that is a general pain with mount namespaces in > general. > > I think the real technical hurdle is finding the mounts t in some random > mount namespace. Once we can do that relatively efficiently the rest > becomes simple. We already have a "struct mountpoint" hashed on the dentry. Chaining mounts on that mountpoint would be trivial. And we need a MNT_VOLATILE flag and that's it. If we fear that traversing the list of mounts on the dentry to check for non-volatile ones then we could also add a separate volatile counter to struct mountpoint and a matching flag to the dentry. But I don't think that's really necessary. Thanks, Miklos -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
